1083 lines
40 KiB
Ruby
1083 lines
40 KiB
Ruby
# frozen_string_literal: true
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module Gitlab
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module Database
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module MigrationHelpers
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BACKGROUND_MIGRATION_BATCH_SIZE = 1000 # Number of rows to process per job
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BACKGROUND_MIGRATION_JOB_BUFFER_SIZE = 1000 # Number of jobs to bulk queue at a time
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# Adds `created_at` and `updated_at` columns with timezone information.
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#
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# This method is an improved version of Rails' built-in method `add_timestamps`.
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#
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# Available options are:
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# default - The default value for the column.
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# null - When set to `true` the column will allow NULL values.
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# The default is to not allow NULL values.
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def add_timestamps_with_timezone(table_name, options = {})
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options[:null] = false if options[:null].nil?
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[:created_at, :updated_at].each do |column_name|
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if options[:default] && transaction_open?
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raise '`add_timestamps_with_timezone` with default value cannot be run inside a transaction. ' \
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'You can disable transactions by calling `disable_ddl_transaction!` ' \
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'in the body of your migration class'
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end
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# If default value is presented, use `add_column_with_default` method instead.
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if options[:default]
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add_column_with_default(
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table_name,
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column_name,
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:datetime_with_timezone,
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default: options[:default],
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allow_null: options[:null]
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)
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else
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add_column(table_name, column_name, :datetime_with_timezone, options)
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end
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end
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end
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# Creates a new index, concurrently when supported
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#
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# On PostgreSQL this method creates an index concurrently, on MySQL this
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# creates a regular index.
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#
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# Example:
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#
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# add_concurrent_index :users, :some_column
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#
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# See Rails' `add_index` for more info on the available arguments.
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def add_concurrent_index(table_name, column_name, options = {})
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if transaction_open?
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raise 'add_concurrent_index can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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if Database.postgresql?
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options = options.merge({ algorithm: :concurrently })
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end
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if index_exists?(table_name, column_name, options)
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Rails.logger.warn "Index not created because it already exists (this may be due to an aborted migration or similar): table_name: #{table_name}, column_name: #{column_name}"
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return
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end
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disable_statement_timeout do
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add_index(table_name, column_name, options)
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end
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end
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# Removes an existed index, concurrently when supported
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#
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# On PostgreSQL this method removes an index concurrently.
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#
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# Example:
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#
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# remove_concurrent_index :users, :some_column
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#
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# See Rails' `remove_index` for more info on the available arguments.
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def remove_concurrent_index(table_name, column_name, options = {})
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if transaction_open?
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raise 'remove_concurrent_index can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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if supports_drop_index_concurrently?
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options = options.merge({ algorithm: :concurrently })
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end
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unless index_exists?(table_name, column_name, options)
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Rails.logger.warn "Index not removed because it does not exist (this may be due to an aborted migration or similar): table_name: #{table_name}, column_name: #{column_name}"
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return
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end
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disable_statement_timeout do
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remove_index(table_name, options.merge({ column: column_name }))
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end
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end
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# Removes an existing index, concurrently when supported
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#
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# On PostgreSQL this method removes an index concurrently.
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#
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# Example:
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#
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# remove_concurrent_index :users, "index_X_by_Y"
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#
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# See Rails' `remove_index` for more info on the available arguments.
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def remove_concurrent_index_by_name(table_name, index_name, options = {})
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if transaction_open?
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raise 'remove_concurrent_index_by_name can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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if supports_drop_index_concurrently?
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options = options.merge({ algorithm: :concurrently })
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end
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unless index_exists_by_name?(table_name, index_name)
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Rails.logger.warn "Index not removed because it does not exist (this may be due to an aborted migration or similar): table_name: #{table_name}, index_name: #{index_name}"
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return
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end
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disable_statement_timeout do
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remove_index(table_name, options.merge({ name: index_name }))
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end
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end
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# Only available on Postgresql >= 9.2
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def supports_drop_index_concurrently?
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return false unless Database.postgresql?
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version = select_one("SELECT current_setting('server_version_num') AS v")['v'].to_i
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version >= 90200
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end
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# Adds a foreign key with only minimal locking on the tables involved.
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#
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# This method only requires minimal locking when using PostgreSQL. When
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# using MySQL this method will use Rails' default `add_foreign_key`.
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#
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# source - The source table containing the foreign key.
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# target - The target table the key points to.
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# column - The name of the column to create the foreign key on.
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# on_delete - The action to perform when associated data is removed,
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# defaults to "CASCADE".
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def add_concurrent_foreign_key(source, target, column:, on_delete: :cascade)
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# Transactions would result in ALTER TABLE locks being held for the
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# duration of the transaction, defeating the purpose of this method.
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if transaction_open?
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raise 'add_concurrent_foreign_key can not be run inside a transaction'
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end
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# While MySQL does allow disabling of foreign keys it has no equivalent
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# of PostgreSQL's "VALIDATE CONSTRAINT". As a result we'll just fall
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# back to the normal foreign key procedure.
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if Database.mysql?
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if foreign_key_exists?(source, target, column: column)
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Rails.logger.warn "Foreign key not created because it exists already " \
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"(this may be due to an aborted migration or similar): " \
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"source: #{source}, target: #{target}, column: #{column}"
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return
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end
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return add_foreign_key(source, target,
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column: column,
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on_delete: on_delete)
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else
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on_delete = 'SET NULL' if on_delete == :nullify
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end
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key_name = concurrent_foreign_key_name(source, column)
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unless foreign_key_exists?(source, target, column: column)
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Rails.logger.warn "Foreign key not created because it exists already " \
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"(this may be due to an aborted migration or similar): " \
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"source: #{source}, target: #{target}, column: #{column}"
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# Using NOT VALID allows us to create a key without immediately
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# validating it. This means we keep the ALTER TABLE lock only for a
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# short period of time. The key _is_ enforced for any newly created
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# data.
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execute <<-EOF.strip_heredoc
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ALTER TABLE #{source}
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ADD CONSTRAINT #{key_name}
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FOREIGN KEY (#{column})
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REFERENCES #{target} (id)
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#{on_delete ? "ON DELETE #{on_delete.upcase}" : ''}
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NOT VALID;
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EOF
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end
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# Validate the existing constraint. This can potentially take a very
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# long time to complete, but fortunately does not lock the source table
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# while running.
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#
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# Note this is a no-op in case the constraint is VALID already
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disable_statement_timeout do
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execute("ALTER TABLE #{source} VALIDATE CONSTRAINT #{key_name};")
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end
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end
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def foreign_key_exists?(source, target = nil, column: nil)
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foreign_keys(source).any? do |key|
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if column
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key.options[:column].to_s == column.to_s
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else
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key.to_table.to_s == target.to_s
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end
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end
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end
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# Returns the name for a concurrent foreign key.
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#
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# PostgreSQL constraint names have a limit of 63 bytes. The logic used
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# here is based on Rails' foreign_key_name() method, which unfortunately
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# is private so we can't rely on it directly.
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def concurrent_foreign_key_name(table, column)
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"fk_#{Digest::SHA256.hexdigest("#{table}_#{column}_fk").first(10)}"
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end
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# Long-running migrations may take more than the timeout allowed by
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# the database. Disable the session's statement timeout to ensure
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# migrations don't get killed prematurely. (PostgreSQL only)
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#
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# There are two possible ways to disable the statement timeout:
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#
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# - Per transaction (this is the preferred and default mode)
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# - Per connection (requires a cleanup after the execution)
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#
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# When using a per connection disable statement, code must be inside
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# a block so we can automatically execute `RESET ALL` after block finishes
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# otherwise the statement will still be disabled until connection is dropped
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# or `RESET ALL` is executed
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def disable_statement_timeout
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# bypass disabled_statement logic when not using postgres, but still execute block when one is given
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unless Database.postgresql?
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if block_given?
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yield
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end
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return
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end
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if block_given?
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begin
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execute('SET statement_timeout TO 0')
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yield
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ensure
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execute('RESET ALL')
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end
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else
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unless transaction_open?
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raise <<~ERROR
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Cannot call disable_statement_timeout() without a transaction open or outside of a transaction block.
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If you don't want to use a transaction wrap your code in a block call:
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disable_statement_timeout { # code that requires disabled statement here }
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This will make sure statement_timeout is disabled before and reset after the block execution is finished.
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ERROR
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end
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execute('SET LOCAL statement_timeout TO 0')
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end
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end
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def true_value
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Database.true_value
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end
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def false_value
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Database.false_value
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end
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# Updates the value of a column in batches.
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#
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# This method updates the table in batches of 5% of the total row count.
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# This method will continue updating rows until no rows remain.
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#
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# When given a block this method will yield two values to the block:
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#
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# 1. An instance of `Arel::Table` for the table that is being updated.
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# 2. The query to run as an Arel object.
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#
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# By supplying a block one can add extra conditions to the queries being
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# executed. Note that the same block is used for _all_ queries.
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#
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# Example:
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#
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# update_column_in_batches(:projects, :foo, 10) do |table, query|
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# query.where(table[:some_column].eq('hello'))
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# end
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#
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# This would result in this method updating only rows where
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# `projects.some_column` equals "hello".
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#
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# table - The name of the table.
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# column - The name of the column to update.
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# value - The value for the column.
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#
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# The `value` argument is typically a literal. To perform a computed
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# update, an Arel literal can be used instead:
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#
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# update_value = Arel.sql('bar * baz')
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#
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# update_column_in_batches(:projects, :foo, update_value) do |table, query|
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# query.where(table[:some_column].eq('hello'))
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# end
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#
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# Rubocop's Metrics/AbcSize metric is disabled for this method as Rubocop
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# determines this method to be too complex while there's no way to make it
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# less "complex" without introducing extra methods (which actually will
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# make things _more_ complex).
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#
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# rubocop: disable Metrics/AbcSize
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def update_column_in_batches(table, column, value)
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if transaction_open?
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raise 'update_column_in_batches can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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table = Arel::Table.new(table)
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count_arel = table.project(Arel.star.count.as('count'))
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count_arel = yield table, count_arel if block_given?
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total = exec_query(count_arel.to_sql).to_hash.first['count'].to_i
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return if total == 0
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# Update in batches of 5% until we run out of any rows to update.
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batch_size = ((total / 100.0) * 5.0).ceil
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max_size = 1000
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# The upper limit is 1000 to ensure we don't lock too many rows. For
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# example, for "merge_requests" even 1% of the table is around 35 000
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# rows for GitLab.com.
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batch_size = max_size if batch_size > max_size
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start_arel = table.project(table[:id]).order(table[:id].asc).take(1)
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start_arel = yield table, start_arel if block_given?
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start_id = exec_query(start_arel.to_sql).to_hash.first['id'].to_i
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loop do
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stop_arel = table.project(table[:id])
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.where(table[:id].gteq(start_id))
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.order(table[:id].asc)
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.take(1)
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.skip(batch_size)
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stop_arel = yield table, stop_arel if block_given?
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stop_row = exec_query(stop_arel.to_sql).to_hash.first
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update_arel = Arel::UpdateManager.new
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.table(table)
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.set([[table[column], value]])
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.where(table[:id].gteq(start_id))
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if stop_row
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stop_id = stop_row['id'].to_i
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start_id = stop_id
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update_arel = update_arel.where(table[:id].lt(stop_id))
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end
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update_arel = yield table, update_arel if block_given?
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execute(update_arel.to_sql)
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# There are no more rows left to update.
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break unless stop_row
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end
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end
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# Adds a column with a default value without locking an entire table.
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#
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# This method runs the following steps:
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#
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# 1. Add the column with a default value of NULL.
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# 2. Change the default value of the column to the specified value.
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# 3. Update all existing rows in batches.
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# 4. Set a `NOT NULL` constraint on the column if desired (the default).
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#
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# These steps ensure a column can be added to a large and commonly used
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# table without locking the entire table for the duration of the table
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# modification.
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#
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# table - The name of the table to update.
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# column - The name of the column to add.
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# type - The column type (e.g. `:integer`).
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# default - The default value for the column.
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# limit - Sets a column limit. For example, for :integer, the default is
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# 4-bytes. Set `limit: 8` to allow 8-byte integers.
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# allow_null - When set to `true` the column will allow NULL values, the
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# default is to not allow NULL values.
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#
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# This method can also take a block which is passed directly to the
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# `update_column_in_batches` method.
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def add_column_with_default(table, column, type, default:, limit: nil, allow_null: false, &block)
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if transaction_open?
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raise 'add_column_with_default can not be run inside a transaction, ' \
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'you can disable transactions by calling disable_ddl_transaction! ' \
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'in the body of your migration class'
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end
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disable_statement_timeout do
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transaction do
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if limit
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add_column(table, column, type, default: nil, limit: limit)
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else
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add_column(table, column, type, default: nil)
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end
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# Changing the default before the update ensures any newly inserted
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# rows already use the proper default value.
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change_column_default(table, column, default)
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end
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begin
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update_column_in_batches(table, column, default, &block)
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change_column_null(table, column, false) unless allow_null
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# We want to rescue _all_ exceptions here, even those that don't inherit
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# from StandardError.
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rescue Exception => error # rubocop: disable all
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remove_column(table, column)
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raise error
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end
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end
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end
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# Renames a column without requiring downtime.
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#
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# Concurrent renames work by using database triggers to ensure both the
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# old and new column are in sync. However, this method will _not_ remove
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# the triggers or the old column automatically; this needs to be done
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# manually in a post-deployment migration. This can be done using the
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# method `cleanup_concurrent_column_rename`.
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#
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# table - The name of the database table containing the column.
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# old - The old column name.
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# new - The new column name.
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# type - The type of the new column. If no type is given the old column's
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# type is used.
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def rename_column_concurrently(table, old, new, type: nil)
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if transaction_open?
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raise 'rename_column_concurrently can not be run inside a transaction'
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end
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check_trigger_permissions!(table)
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old_col = column_for(table, old)
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new_type = type || old_col.type
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add_column(table, new, new_type,
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limit: old_col.limit,
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precision: old_col.precision,
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scale: old_col.scale)
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# We set the default value _after_ adding the column so we don't end up
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# updating any existing data with the default value. This isn't
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# necessary since we copy over old values further down.
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change_column_default(table, new, old_col.default) if old_col.default
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install_rename_triggers(table, old, new)
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update_column_in_batches(table, new, Arel::Table.new(table)[old])
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change_column_null(table, new, false) unless old_col.null
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copy_indexes(table, old, new)
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copy_foreign_keys(table, old, new)
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end
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|
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# Installs triggers in a table that keep a new column in sync with an old
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# one.
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#
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# table - The name of the table to install the trigger in.
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# old_column - The name of the old column.
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# new_column - The name of the new column.
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def install_rename_triggers(table, old_column, new_column)
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trigger_name = rename_trigger_name(table, old_column, new_column)
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quoted_table = quote_table_name(table)
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quoted_old = quote_column_name(old_column)
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quoted_new = quote_column_name(new_column)
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|
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if Database.postgresql?
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install_rename_triggers_for_postgresql(trigger_name, quoted_table,
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quoted_old, quoted_new)
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else
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install_rename_triggers_for_mysql(trigger_name, quoted_table,
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quoted_old, quoted_new)
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end
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end
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|
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# Changes the type of a column concurrently.
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|
#
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# table - The table containing the column.
|
|
# column - The name of the column to change.
|
|
# new_type - The new column type.
|
|
def change_column_type_concurrently(table, column, new_type)
|
|
temp_column = "#{column}_for_type_change"
|
|
|
|
rename_column_concurrently(table, column, temp_column, type: new_type)
|
|
end
|
|
|
|
# Performs cleanup of a concurrent type change.
|
|
#
|
|
# table - The table containing the column.
|
|
# column - The name of the column to change.
|
|
# new_type - The new column type.
|
|
def cleanup_concurrent_column_type_change(table, column)
|
|
temp_column = "#{column}_for_type_change"
|
|
|
|
transaction do
|
|
# This has to be performed in a transaction as otherwise we might have
|
|
# inconsistent data.
|
|
cleanup_concurrent_column_rename(table, column, temp_column)
|
|
rename_column(table, temp_column, column)
|
|
end
|
|
end
|
|
|
|
# Cleans up a concurrent column name.
|
|
#
|
|
# This method takes care of removing previously installed triggers as well
|
|
# as removing the old column.
|
|
#
|
|
# table - The name of the database table.
|
|
# old - The name of the old column.
|
|
# new - The name of the new column.
|
|
def cleanup_concurrent_column_rename(table, old, new)
|
|
trigger_name = rename_trigger_name(table, old, new)
|
|
|
|
check_trigger_permissions!(table)
|
|
|
|
if Database.postgresql?
|
|
remove_rename_triggers_for_postgresql(table, trigger_name)
|
|
else
|
|
remove_rename_triggers_for_mysql(trigger_name)
|
|
end
|
|
|
|
remove_column(table, old)
|
|
end
|
|
|
|
# Changes the column type of a table using a background migration.
|
|
#
|
|
# Because this method uses a background migration it's more suitable for
|
|
# large tables. For small tables it's better to use
|
|
# `change_column_type_concurrently` since it can complete its work in a
|
|
# much shorter amount of time and doesn't rely on Sidekiq.
|
|
#
|
|
# Example usage:
|
|
#
|
|
# class Issue < ActiveRecord::Base
|
|
# self.table_name = 'issues'
|
|
#
|
|
# include EachBatch
|
|
#
|
|
# def self.to_migrate
|
|
# where('closed_at IS NOT NULL')
|
|
# end
|
|
# end
|
|
#
|
|
# change_column_type_using_background_migration(
|
|
# Issue.to_migrate,
|
|
# :closed_at,
|
|
# :datetime_with_timezone
|
|
# )
|
|
#
|
|
# Reverting a migration like this is done exactly the same way, just with
|
|
# a different type to migrate to (e.g. `:datetime` in the above example).
|
|
#
|
|
# relation - An ActiveRecord relation to use for scheduling jobs and
|
|
# figuring out what table we're modifying. This relation _must_
|
|
# have the EachBatch module included.
|
|
#
|
|
# column - The name of the column for which the type will be changed.
|
|
#
|
|
# new_type - The new type of the column.
|
|
#
|
|
# batch_size - The number of rows to schedule in a single background
|
|
# migration.
|
|
#
|
|
# interval - The time interval between every background migration.
|
|
def change_column_type_using_background_migration(
|
|
relation,
|
|
column,
|
|
new_type,
|
|
batch_size: 10_000,
|
|
interval: 10.minutes
|
|
)
|
|
|
|
unless relation.model < EachBatch
|
|
raise TypeError, 'The relation must include the EachBatch module'
|
|
end
|
|
|
|
temp_column = "#{column}_for_type_change"
|
|
table = relation.table_name
|
|
max_index = 0
|
|
|
|
add_column(table, temp_column, new_type)
|
|
install_rename_triggers(table, column, temp_column)
|
|
|
|
# Schedule the jobs that will copy the data from the old column to the
|
|
# new one. Rows with NULL values in our source column are skipped since
|
|
# the target column is already NULL at this point.
|
|
relation.where.not(column => nil).each_batch(of: batch_size) do |batch, index|
|
|
start_id, end_id = batch.pluck('MIN(id), MAX(id)').first
|
|
max_index = index
|
|
|
|
BackgroundMigrationWorker.perform_in(
|
|
index * interval,
|
|
'CopyColumn',
|
|
[table, column, temp_column, start_id, end_id]
|
|
)
|
|
end
|
|
|
|
# Schedule the renaming of the column to happen (initially) 1 hour after
|
|
# the last batch finished.
|
|
BackgroundMigrationWorker.perform_in(
|
|
(max_index * interval) + 1.hour,
|
|
'CleanupConcurrentTypeChange',
|
|
[table, column, temp_column]
|
|
)
|
|
|
|
if perform_background_migration_inline?
|
|
# To ensure the schema is up to date immediately we perform the
|
|
# migration inline in dev / test environments.
|
|
Gitlab::BackgroundMigration.steal('CopyColumn')
|
|
Gitlab::BackgroundMigration.steal('CleanupConcurrentTypeChange')
|
|
end
|
|
end
|
|
|
|
# Renames a column using a background migration.
|
|
#
|
|
# Because this method uses a background migration it's more suitable for
|
|
# large tables. For small tables it's better to use
|
|
# `rename_column_concurrently` since it can complete its work in a much
|
|
# shorter amount of time and doesn't rely on Sidekiq.
|
|
#
|
|
# Example usage:
|
|
#
|
|
# rename_column_using_background_migration(
|
|
# :users,
|
|
# :feed_token,
|
|
# :rss_token
|
|
# )
|
|
#
|
|
# table - The name of the database table containing the column.
|
|
#
|
|
# old - The old column name.
|
|
#
|
|
# new - The new column name.
|
|
#
|
|
# type - The type of the new column. If no type is given the old column's
|
|
# type is used.
|
|
#
|
|
# batch_size - The number of rows to schedule in a single background
|
|
# migration.
|
|
#
|
|
# interval - The time interval between every background migration.
|
|
def rename_column_using_background_migration(
|
|
table,
|
|
old_column,
|
|
new_column,
|
|
type: nil,
|
|
batch_size: 10_000,
|
|
interval: 10.minutes
|
|
)
|
|
|
|
check_trigger_permissions!(table)
|
|
|
|
old_col = column_for(table, old_column)
|
|
new_type = type || old_col.type
|
|
max_index = 0
|
|
|
|
add_column(table, new_column, new_type,
|
|
limit: old_col.limit,
|
|
precision: old_col.precision,
|
|
scale: old_col.scale)
|
|
|
|
# We set the default value _after_ adding the column so we don't end up
|
|
# updating any existing data with the default value. This isn't
|
|
# necessary since we copy over old values further down.
|
|
change_column_default(table, new_column, old_col.default) if old_col.default
|
|
|
|
install_rename_triggers(table, old_column, new_column)
|
|
|
|
model = Class.new(ActiveRecord::Base) do
|
|
self.table_name = table
|
|
|
|
include ::EachBatch
|
|
end
|
|
|
|
# Schedule the jobs that will copy the data from the old column to the
|
|
# new one. Rows with NULL values in our source column are skipped since
|
|
# the target column is already NULL at this point.
|
|
model.where.not(old_column => nil).each_batch(of: batch_size) do |batch, index|
|
|
start_id, end_id = batch.pluck('MIN(id), MAX(id)').first
|
|
max_index = index
|
|
|
|
BackgroundMigrationWorker.perform_in(
|
|
index * interval,
|
|
'CopyColumn',
|
|
[table, old_column, new_column, start_id, end_id]
|
|
)
|
|
end
|
|
|
|
# Schedule the renaming of the column to happen (initially) 1 hour after
|
|
# the last batch finished.
|
|
BackgroundMigrationWorker.perform_in(
|
|
(max_index * interval) + 1.hour,
|
|
'CleanupConcurrentRename',
|
|
[table, old_column, new_column]
|
|
)
|
|
|
|
if perform_background_migration_inline?
|
|
# To ensure the schema is up to date immediately we perform the
|
|
# migration inline in dev / test environments.
|
|
Gitlab::BackgroundMigration.steal('CopyColumn')
|
|
Gitlab::BackgroundMigration.steal('CleanupConcurrentRename')
|
|
end
|
|
end
|
|
|
|
def perform_background_migration_inline?
|
|
Rails.env.test? || Rails.env.development?
|
|
end
|
|
|
|
# Performs a concurrent column rename when using PostgreSQL.
|
|
def install_rename_triggers_for_postgresql(trigger, table, old, new)
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE OR REPLACE FUNCTION #{trigger}()
|
|
RETURNS trigger AS
|
|
$BODY$
|
|
BEGIN
|
|
NEW.#{new} := NEW.#{old};
|
|
RETURN NEW;
|
|
END;
|
|
$BODY$
|
|
LANGUAGE 'plpgsql'
|
|
VOLATILE
|
|
EOF
|
|
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE TRIGGER #{trigger}
|
|
BEFORE INSERT OR UPDATE
|
|
ON #{table}
|
|
FOR EACH ROW
|
|
EXECUTE PROCEDURE #{trigger}()
|
|
EOF
|
|
end
|
|
|
|
# Installs the triggers necessary to perform a concurrent column rename on
|
|
# MySQL.
|
|
def install_rename_triggers_for_mysql(trigger, table, old, new)
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE TRIGGER #{trigger}_insert
|
|
BEFORE INSERT
|
|
ON #{table}
|
|
FOR EACH ROW
|
|
SET NEW.#{new} = NEW.#{old}
|
|
EOF
|
|
|
|
execute <<-EOF.strip_heredoc
|
|
CREATE TRIGGER #{trigger}_update
|
|
BEFORE UPDATE
|
|
ON #{table}
|
|
FOR EACH ROW
|
|
SET NEW.#{new} = NEW.#{old}
|
|
EOF
|
|
end
|
|
|
|
# Removes the triggers used for renaming a PostgreSQL column concurrently.
|
|
def remove_rename_triggers_for_postgresql(table, trigger)
|
|
execute("DROP TRIGGER IF EXISTS #{trigger} ON #{table}")
|
|
execute("DROP FUNCTION IF EXISTS #{trigger}()")
|
|
end
|
|
|
|
# Removes the triggers used for renaming a MySQL column concurrently.
|
|
def remove_rename_triggers_for_mysql(trigger)
|
|
execute("DROP TRIGGER IF EXISTS #{trigger}_insert")
|
|
execute("DROP TRIGGER IF EXISTS #{trigger}_update")
|
|
end
|
|
|
|
# Returns the (base) name to use for triggers when renaming columns.
|
|
def rename_trigger_name(table, old, new)
|
|
'trigger_' + Digest::SHA256.hexdigest("#{table}_#{old}_#{new}").first(12)
|
|
end
|
|
|
|
# Returns an Array containing the indexes for the given column
|
|
def indexes_for(table, column)
|
|
column = column.to_s
|
|
|
|
indexes(table).select { |index| index.columns.include?(column) }
|
|
end
|
|
|
|
# Returns an Array containing the foreign keys for the given column.
|
|
def foreign_keys_for(table, column)
|
|
column = column.to_s
|
|
|
|
foreign_keys(table).select { |fk| fk.column == column }
|
|
end
|
|
|
|
# Copies all indexes for the old column to a new column.
|
|
#
|
|
# table - The table containing the columns and indexes.
|
|
# old - The old column.
|
|
# new - The new column.
|
|
def copy_indexes(table, old, new)
|
|
old = old.to_s
|
|
new = new.to_s
|
|
|
|
indexes_for(table, old).each do |index|
|
|
new_columns = index.columns.map do |column|
|
|
column == old ? new : column
|
|
end
|
|
|
|
# This is necessary as we can't properly rename indexes such as
|
|
# "ci_taggings_idx".
|
|
unless index.name.include?(old)
|
|
raise "The index #{index.name} can not be copied as it does not "\
|
|
"mention the old column. You have to rename this index manually first."
|
|
end
|
|
|
|
name = index.name.gsub(old, new)
|
|
|
|
options = {
|
|
unique: index.unique,
|
|
name: name,
|
|
length: index.lengths,
|
|
order: index.orders
|
|
}
|
|
|
|
# These options are not supported by MySQL, so we only add them if
|
|
# they were previously set.
|
|
options[:using] = index.using if index.using
|
|
options[:where] = index.where if index.where
|
|
|
|
unless index.opclasses.blank?
|
|
opclasses = index.opclasses.dup
|
|
|
|
# Copy the operator classes for the old column (if any) to the new
|
|
# column.
|
|
opclasses[new] = opclasses.delete(old) if opclasses[old]
|
|
|
|
options[:opclasses] = opclasses
|
|
end
|
|
|
|
add_concurrent_index(table, new_columns, options)
|
|
end
|
|
end
|
|
|
|
# Copies all foreign keys for the old column to the new column.
|
|
#
|
|
# table - The table containing the columns and indexes.
|
|
# old - The old column.
|
|
# new - The new column.
|
|
def copy_foreign_keys(table, old, new)
|
|
foreign_keys_for(table, old).each do |fk|
|
|
add_concurrent_foreign_key(fk.from_table,
|
|
fk.to_table,
|
|
column: new,
|
|
on_delete: fk.on_delete)
|
|
end
|
|
end
|
|
|
|
# Returns the column for the given table and column name.
|
|
def column_for(table, name)
|
|
name = name.to_s
|
|
|
|
columns(table).find { |column| column.name == name }
|
|
end
|
|
|
|
# This will replace the first occurrence of a string in a column with
|
|
# the replacement
|
|
# On postgresql we can use `regexp_replace` for that.
|
|
# On mysql we find the location of the pattern, and overwrite it
|
|
# with the replacement
|
|
def replace_sql(column, pattern, replacement)
|
|
quoted_pattern = Arel::Nodes::Quoted.new(pattern.to_s)
|
|
quoted_replacement = Arel::Nodes::Quoted.new(replacement.to_s)
|
|
|
|
if Database.mysql?
|
|
locate = Arel::Nodes::NamedFunction
|
|
.new('locate', [quoted_pattern, column])
|
|
insert_in_place = Arel::Nodes::NamedFunction
|
|
.new('insert', [column, locate, pattern.size, quoted_replacement])
|
|
|
|
Arel::Nodes::SqlLiteral.new(insert_in_place.to_sql)
|
|
else
|
|
replace = Arel::Nodes::NamedFunction
|
|
.new("regexp_replace", [column, quoted_pattern, quoted_replacement])
|
|
Arel::Nodes::SqlLiteral.new(replace.to_sql)
|
|
end
|
|
end
|
|
|
|
def remove_foreign_key_without_error(*args)
|
|
remove_foreign_key(*args)
|
|
rescue ArgumentError
|
|
end
|
|
|
|
def sidekiq_queue_migrate(queue_from, to:)
|
|
while sidekiq_queue_length(queue_from) > 0
|
|
Sidekiq.redis do |conn|
|
|
conn.rpoplpush "queue:#{queue_from}", "queue:#{to}"
|
|
end
|
|
end
|
|
end
|
|
|
|
def sidekiq_queue_length(queue_name)
|
|
Sidekiq.redis do |conn|
|
|
conn.llen("queue:#{queue_name}")
|
|
end
|
|
end
|
|
|
|
def check_trigger_permissions!(table)
|
|
unless Grant.create_and_execute_trigger?(table)
|
|
dbname = Database.database_name
|
|
user = Database.username
|
|
|
|
raise <<-EOF
|
|
Your database user is not allowed to create, drop, or execute triggers on the
|
|
table #{table}.
|
|
|
|
If you are using PostgreSQL you can solve this by logging in to the GitLab
|
|
database (#{dbname}) using a super user and running:
|
|
|
|
ALTER #{user} WITH SUPERUSER
|
|
|
|
For MySQL you instead need to run:
|
|
|
|
GRANT ALL PRIVILEGES ON #{dbname}.* TO #{user}@'%'
|
|
|
|
Both queries will grant the user super user permissions, ensuring you don't run
|
|
into similar problems in the future (e.g. when new tables are created).
|
|
EOF
|
|
end
|
|
end
|
|
|
|
# Bulk queues background migration jobs for an entire table, batched by ID range.
|
|
# "Bulk" meaning many jobs will be pushed at a time for efficiency.
|
|
# If you need a delay interval per job, then use `queue_background_migration_jobs_by_range_at_intervals`.
|
|
#
|
|
# model_class - The table being iterated over
|
|
# job_class_name - The background migration job class as a string
|
|
# batch_size - The maximum number of rows per job
|
|
#
|
|
# Example:
|
|
#
|
|
# class Route < ActiveRecord::Base
|
|
# include EachBatch
|
|
# self.table_name = 'routes'
|
|
# end
|
|
#
|
|
# bulk_queue_background_migration_jobs_by_range(Route, 'ProcessRoutes')
|
|
#
|
|
# Where the model_class includes EachBatch, and the background migration exists:
|
|
#
|
|
# class Gitlab::BackgroundMigration::ProcessRoutes
|
|
# def perform(start_id, end_id)
|
|
# # do something
|
|
# end
|
|
# end
|
|
def bulk_queue_background_migration_jobs_by_range(model_class, job_class_name, batch_size: BACKGROUND_MIGRATION_BATCH_SIZE)
|
|
raise "#{model_class} does not have an ID to use for batch ranges" unless model_class.column_names.include?('id')
|
|
|
|
jobs = []
|
|
table_name = model_class.quoted_table_name
|
|
|
|
model_class.each_batch(of: batch_size) do |relation|
|
|
start_id, end_id = relation.pluck("MIN(#{table_name}.id), MAX(#{table_name}.id)").first
|
|
|
|
if jobs.length >= BACKGROUND_MIGRATION_JOB_BUFFER_SIZE
|
|
# Note: This code path generally only helps with many millions of rows
|
|
# We push multiple jobs at a time to reduce the time spent in
|
|
# Sidekiq/Redis operations. We're using this buffer based approach so we
|
|
# don't need to run additional queries for every range.
|
|
BackgroundMigrationWorker.bulk_perform_async(jobs)
|
|
jobs.clear
|
|
end
|
|
|
|
jobs << [job_class_name, [start_id, end_id]]
|
|
end
|
|
|
|
BackgroundMigrationWorker.bulk_perform_async(jobs) unless jobs.empty?
|
|
end
|
|
|
|
# Queues background migration jobs for an entire table, batched by ID range.
|
|
# Each job is scheduled with a `delay_interval` in between.
|
|
# If you use a small interval, then some jobs may run at the same time.
|
|
#
|
|
# model_class - The table or relation being iterated over
|
|
# job_class_name - The background migration job class as a string
|
|
# delay_interval - The duration between each job's scheduled time (must respond to `to_f`)
|
|
# batch_size - The maximum number of rows per job
|
|
#
|
|
# Example:
|
|
#
|
|
# class Route < ActiveRecord::Base
|
|
# include EachBatch
|
|
# self.table_name = 'routes'
|
|
# end
|
|
#
|
|
# queue_background_migration_jobs_by_range_at_intervals(Route, 'ProcessRoutes', 1.minute)
|
|
#
|
|
# Where the model_class includes EachBatch, and the background migration exists:
|
|
#
|
|
# class Gitlab::BackgroundMigration::ProcessRoutes
|
|
# def perform(start_id, end_id)
|
|
# # do something
|
|
# end
|
|
# end
|
|
def queue_background_migration_jobs_by_range_at_intervals(model_class, job_class_name, delay_interval, batch_size: BACKGROUND_MIGRATION_BATCH_SIZE)
|
|
raise "#{model_class} does not have an ID to use for batch ranges" unless model_class.column_names.include?('id')
|
|
|
|
# To not overload the worker too much we enforce a minimum interval both
|
|
# when scheduling and performing jobs.
|
|
if delay_interval < BackgroundMigrationWorker.minimum_interval
|
|
delay_interval = BackgroundMigrationWorker.minimum_interval
|
|
end
|
|
|
|
model_class.each_batch(of: batch_size) do |relation, index|
|
|
start_id, end_id = relation.pluck('MIN(id), MAX(id)').first
|
|
|
|
# `BackgroundMigrationWorker.bulk_perform_in` schedules all jobs for
|
|
# the same time, which is not helpful in most cases where we wish to
|
|
# spread the work over time.
|
|
BackgroundMigrationWorker.perform_in(delay_interval * index, job_class_name, [start_id, end_id])
|
|
end
|
|
end
|
|
|
|
# Fetches indexes on a column by name for postgres.
|
|
#
|
|
# This will include indexes using an expression on the column, for example:
|
|
# `CREATE INDEX CONCURRENTLY index_name ON table (LOWER(column));`
|
|
#
|
|
# For mysql, it falls back to the default ActiveRecord implementation that
|
|
# will not find custom indexes. But it will select by name without passing
|
|
# a column.
|
|
#
|
|
# We can remove this when upgrading to Rails 5 with an updated `index_exists?`:
|
|
# - https://github.com/rails/rails/commit/edc2b7718725016e988089b5fb6d6fb9d6e16882
|
|
#
|
|
# Or this can be removed when we no longer support postgres < 9.5, so we
|
|
# can use `CREATE INDEX IF NOT EXISTS`.
|
|
def index_exists_by_name?(table, index)
|
|
# We can't fall back to the normal `index_exists?` method because that
|
|
# does not find indexes without passing a column name.
|
|
if indexes(table).map(&:name).include?(index.to_s)
|
|
true
|
|
elsif Gitlab::Database.postgresql?
|
|
postgres_exists_by_name?(table, index)
|
|
else
|
|
false
|
|
end
|
|
end
|
|
|
|
def postgres_exists_by_name?(table, name)
|
|
index_sql = <<~SQL
|
|
SELECT COUNT(*)
|
|
FROM pg_index
|
|
JOIN pg_class i ON (indexrelid=i.oid)
|
|
JOIN pg_class t ON (indrelid=t.oid)
|
|
WHERE i.relname = '#{name}' AND t.relname = '#{table}'
|
|
SQL
|
|
|
|
connection.select_value(index_sql).to_i > 0
|
|
end
|
|
|
|
def mysql_compatible_index_length
|
|
Gitlab::Database.mysql? ? 20 : nil
|
|
end
|
|
end
|
|
end
|
|
end
|