756 lines
27 KiB
Ruby
756 lines
27 KiB
Ruby
# frozen_string_literal: true
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# This file is copied almost entirely from GitLab, which has done a large
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# amount of work to ensure that migrations can happen with minimal downtime.
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# Many thanks to those engineers.
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# Changes have been made to remove dependencies on other GitLab files and to
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# shorten temporary column names.
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# Documentation on using these functions (and why one might do so):
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# https://gitlab.com/gitlab-org/gitlab-foss/-/blob/master/doc/development/database/avoiding_downtime_in_migrations.md
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# The original file (since updated):
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# https://gitlab.com/gitlab-org/gitlab-foss/-/blob/master/lib/gitlab/database/migration_helpers.rb
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# It is licensed as follows:
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# Copyright (c) 2011-present GitLab B.V.
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#
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# Permission is hereby granted, free of charge, to any person obtaining a copy
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# of this software and associated documentation files (the "Software"), to deal
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# in the Software without restriction, including without limitation the rights
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# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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# copies of the Software, and to permit persons to whom the Software is
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# furnished to do so, subject to the following conditions:
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# The above copyright notice and this permission notice shall be included in all
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# copies or substantial portions of the Software.
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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# SOFTWARE.
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# This is bad form, but there are enough differences that it's impractical to do
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# otherwise:
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module Mastodon
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module MigrationHelpers
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class CorruptionError < StandardError
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attr_reader :index_name
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def initialize(index_name)
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@index_name = index_name
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super "The index `#{index_name}` seems to be corrupted, it contains duplicate rows. " \
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'For information on how to fix this, see our documentation: ' \
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'https://docs.joinmastodon.org/admin/troubleshooting/index-corruption/'
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end
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def cause
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nil
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end
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def backtrace
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[]
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end
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end
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# Model that can be used for querying permissions of a SQL user.
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class Grant < ActiveRecord::Base
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self.table_name = 'information_schema.role_table_grants'
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def self.scope_to_current_user
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where('grantee = user')
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end
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# Returns true if the current user can create and execute triggers on the
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# given table.
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def self.create_and_execute_trigger?(table)
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priv = where(privilege_type: 'TRIGGER', table_name: table)
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priv.scope_to_current_user.any?
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end
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end
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# Gets an estimated number of rows for a table
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def estimate_rows_in_table(table_name)
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exec_query('SELECT reltuples FROM pg_class WHERE relname = ' +
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"'#{table_name}'").to_a.first['reltuples']
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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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options = options.merge({ algorithm: :concurrently })
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disable_statement_timeout
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add_index(table_name, column_name, **options)
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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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options = options.merge({ algorithm: :concurrently })
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disable_statement_timeout
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remove_index(table_name, **options.merge({ column: column_name }))
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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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options = options.merge({ algorithm: :concurrently })
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disable_statement_timeout
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remove_index(table_name, **options.merge({ name: index_name }))
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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, target_col: 'id')
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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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on_delete = 'SET NULL' if on_delete == :nullify
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disable_statement_timeout
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key_name = concurrent_foreign_key_name(source, column, target_col)
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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} (#{target_col})
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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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# 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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execute("ALTER TABLE #{source} VALIDATE CONSTRAINT #{key_name};")
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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, target_col)
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"fk_#{Digest::SHA256.hexdigest("#{table}_#{column}_#{target_col}_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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def disable_statement_timeout
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execute('SET statement_timeout TO 0')
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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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# 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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def update_column_in_batches(table_name, 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_name)
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total = estimate_rows_in_table(table_name).to_i
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if total < 1
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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_ary.first['count'].to_i
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return if total == 0
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end
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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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first_row = exec_query(start_arel.to_sql).to_ary.first
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# In case there are no rows but we didn't catch it in the estimated size:
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return unless first_row
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start_id = first_row['id'].to_i
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say "Migrating #{table_name}.#{column} (~#{total.to_i} rows)"
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started_time = Time.zone.now
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last_time = Time.zone.now
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migrated = 0
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loop do
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stop_row = nil
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suppress_messages 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_ary.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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end
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migrated += batch_size
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if Time.zone.now - last_time > 1
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status = "Migrated #{migrated} rows"
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percentage = 100.0 * migrated / total
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status += " (~#{sprintf('%.2f', percentage)}%, "
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remaining_time = (100.0 - percentage) * (Time.zone.now - started_time) / percentage
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status += "#{(remaining_time / 60).to_i}:"
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status += sprintf('%02d', remaining_time.to_i % 60)
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status += ' remaining, '
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# Tell users not to interrupt if we're almost done.
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if remaining_time > 10
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status += 'safe to interrupt'
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else
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status += 'DO NOT interrupt'
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end
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status += ')'
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say status, true
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last_time = Time.zone.now
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end
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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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# 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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trigger_name = rename_trigger_name(table, old, new)
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# If we were in the middle of update_column_in_batches, we should remove
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# the old column and start over, as we have no idea where we were.
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if column_for(table, new)
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remove_rename_triggers_for_postgresql(table, trigger_name)
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remove_column(table, new)
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end
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old_col = column_for(table, old)
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new_type = type || old_col.type
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col_opts = {
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precision: old_col.precision,
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scale: old_col.scale,
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}
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# We may be trying to reset the limit on an integer column type, so let
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# Rails handle that.
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unless [:bigint, :integer].include?(new_type)
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col_opts[:limit] = old_col.limit
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end
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add_column(table, new, new_type, **col_opts)
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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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quoted_table = quote_table_name(table)
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quoted_old = quote_column_name(old)
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quoted_new = quote_column_name(new)
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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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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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# Changes the type of a column concurrently.
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#
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# table - The table containing the column.
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# column - The name of the column to change.
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# new_type - The new column type.
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def change_column_type_concurrently(table, column, new_type)
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temp_column = rename_column_name(column)
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rename_column_concurrently(table, column, temp_column, type: new_type)
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# Primary keys don't necessarily have an associated index.
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if ActiveRecord::Base.get_primary_key(table) == column.to_s
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old_pk_index_name = "index_#{table}_on_#{column}"
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new_pk_index_name = "index_#{table}_on_#{column}_cm"
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unless indexes_for(table, column).find{|i| i.name == old_pk_index_name}
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add_concurrent_index(table, [temp_column],
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unique: true,
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name: new_pk_index_name
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)
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end
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end
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end
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# Performs cleanup of a concurrent type change.
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#
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# table - The table containing the column.
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# column - The name of the column to change.
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# new_type - The new column type.
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def cleanup_concurrent_column_type_change(table, column)
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temp_column = rename_column_name(column)
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# Wait for the indices to be built
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indexes_for(table, column).each do |index|
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expected_name = index.name + '_cm'
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puts "Waiting for index #{expected_name}"
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sleep 1 until indexes_for(table, temp_column).find {|i| i.name == expected_name }
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end
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was_primary = (ActiveRecord::Base.get_primary_key(table) == column.to_s)
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old_default_fn = column_for(table, column).default_function
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old_fks = []
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if was_primary
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# Get any foreign keys pointing at this column we need to recreate, and
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# remove the old ones.
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# Based on code from:
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# http://errorbank.blogspot.com/2011/03/list-all-foreign-keys-references-for.html
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old_fks_res = execute <<-EOF.strip_heredoc
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select m.relname as src_table,
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(select a.attname
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from pg_attribute a
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where a.attrelid = m.oid
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and a.attnum = o.conkey[1]
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and a.attisdropped = false) as src_col,
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o.conname as name,
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o.confdeltype as on_delete
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from pg_constraint o
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left join pg_class f on f.oid = o.confrelid
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left join pg_class c on c.oid = o.conrelid
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left join pg_class m on m.oid = o.conrelid
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where o.contype = 'f'
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and o.conrelid in (
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select oid from pg_class c where c.relkind = 'r')
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and f.relname = '#{table}';
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EOF
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old_fks = old_fks_res.to_a
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old_fks.each do |old_fk|
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add_concurrent_foreign_key(
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old_fk['src_table'],
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table,
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column: old_fk['src_col'],
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target_col: temp_column,
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on_delete: extract_foreign_key_action(old_fk['on_delete'])
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)
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remove_foreign_key(old_fk['src_table'], name: old_fk['name'])
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end
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end
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# If there was a sequence owned by the old column, make it owned by the
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# new column, as it will otherwise be deleted when we get rid of the
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# old column.
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if (seq_match = /^nextval\('([^']*)'(::text|::regclass)?\)/.match(old_default_fn))
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seq_name = seq_match[1]
|
|
execute("ALTER SEQUENCE #{seq_name} OWNED BY #{table}.#{temp_column}")
|
|
end
|
|
|
|
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)
|
|
|
|
# If there was an old default function, we didn't copy it. Do that now
|
|
# in the transaction, so we don't miss anything.
|
|
change_column_default(table, column, -> { old_default_fn }) if old_default_fn
|
|
end
|
|
|
|
# Rename any indices back to what they should be.
|
|
indexes_for(table, column).each do |index|
|
|
next unless index.name.end_with?('_cm')
|
|
|
|
real_index_name = index.name.sub(/_cm$/, '')
|
|
rename_index(table, index.name, real_index_name)
|
|
end
|
|
|
|
# Rename any foreign keys back to names based on the real column.
|
|
foreign_keys_for(table, column).each do |fk|
|
|
old_fk_name = concurrent_foreign_key_name(fk.from_table, temp_column, 'id')
|
|
new_fk_name = concurrent_foreign_key_name(fk.from_table, column, 'id')
|
|
execute("ALTER TABLE #{fk.from_table} RENAME CONSTRAINT " +
|
|
"#{old_fk_name} TO #{new_fk_name}")
|
|
end
|
|
|
|
# Rename any foreign keys from other tables to names based on the real
|
|
# column.
|
|
old_fks.each do |old_fk|
|
|
old_fk_name = concurrent_foreign_key_name(old_fk['src_table'],
|
|
old_fk['src_col'], temp_column)
|
|
new_fk_name = concurrent_foreign_key_name(old_fk['src_table'],
|
|
old_fk['src_col'], column)
|
|
execute("ALTER TABLE #{old_fk['src_table']} RENAME CONSTRAINT " +
|
|
"#{old_fk_name} TO #{new_fk_name}")
|
|
end
|
|
|
|
# If the old column was a primary key, mark the new one as a primary key.
|
|
if was_primary
|
|
execute("ALTER TABLE #{table} ADD PRIMARY KEY USING INDEX " +
|
|
"index_#{table}_on_#{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)
|
|
|
|
remove_rename_triggers_for_postgresql(table, trigger_name)
|
|
|
|
remove_column(table, old)
|
|
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 the name to use for temporary rename columns.
|
|
def rename_column_name(base)
|
|
base.to_s + '_cm'
|
|
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".
|
|
name = index.name + '_cm'
|
|
|
|
# If the order contained the old column, map it to the new one.
|
|
order = index.orders
|
|
if order.key?(old)
|
|
order[new] = order.delete(old)
|
|
end
|
|
|
|
options = {
|
|
unique: index.unique,
|
|
name: name,
|
|
length: index.lengths,
|
|
order: order
|
|
}
|
|
|
|
# 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
|
|
|
|
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
|
|
|
|
# Update the configuration of an index by creating a new one and then
|
|
# removing the old one
|
|
def update_index(table_name, index_name, columns, **index_options)
|
|
if index_name_exists?(table_name, "#{index_name}_new") && index_name_exists?(table_name, index_name)
|
|
remove_index table_name, name: "#{index_name}_new"
|
|
elsif index_name_exists?(table_name, "#{index_name}_new")
|
|
# Very unlikely case where the script has been interrupted during/after removal but before renaming
|
|
rename_index table_name, "#{index_name}_new", index_name
|
|
end
|
|
|
|
begin
|
|
add_index table_name, columns, **index_options.merge(name: "#{index_name}_new", algorithm: :concurrently)
|
|
rescue ActiveRecord::RecordNotUnique
|
|
remove_index table_name, name: "#{index_name}_new"
|
|
raise CorruptionError.new(index_name)
|
|
end
|
|
|
|
remove_index table_name, name: index_name if index_name_exists?(table_name, index_name)
|
|
rename_index table_name, "#{index_name}_new", index_name
|
|
end
|
|
|
|
def check_trigger_permissions!(table)
|
|
unless Grant.create_and_execute_trigger?(table)
|
|
dbname = ActiveRecord::Base.configurations[Rails.env]['database']
|
|
user = ActiveRecord::Base.configurations[Rails.env]['username'] || ENV['USER']
|
|
|
|
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 Mastodon
|
|
database (#{dbname}) using a super user and running:
|
|
|
|
ALTER USER #{user} WITH SUPERUSER
|
|
|
|
The query 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
|
|
|
|
private
|
|
|
|
# https://github.com/rails/rails/blob/v5.2.0/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb#L678-L684
|
|
def extract_foreign_key_action(specifier)
|
|
case specifier
|
|
when 'c'; :cascade
|
|
when 'n'; :nullify
|
|
when 'r'; :restrict
|
|
end
|
|
end
|
|
end
|
|
end
|