instance method
remove_column
Ruby on Rails edge
Signature
remove_column(table_name, column_name, type = nil, **options)Removes the column from the table definition.
remove_column(:suppliers, :qualification)
The type and options parameters will be ignored if present. It can be helpful to provide these in a migration’s change method so it can be reverted. In that case, type and options will be used by #add_column. Depending on the database you’re using, indexes using this column may be automatically removed or modified to remove this column from the index.
If the options provided include an if_exists key, it will be used to check if the column does not exist. This will silently ignore the migration rather than raising if the column was already removed.
remove_column(:suppliers, :qualification, if_exists: true)
Removes the column with a specific algorithm and lock mode:
remove_column(:suppliers, :qualification, algorithm: :inplace, lock: :none)
Note: only supported by MySQL.
Parameters
-
table_namereq -
column_namereq -
typeopt = nil -
optionskeyrest
Source
# File activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb, line 761
def remove_column(table_name, column_name, type = nil, **options)
return if options[:if_exists] == true && !column_exists?(table_name, column_name)
at = build_alter_table_definition(table_name)
at.remove_column(column_name)
execute_alter_table(at)
end
Defined in activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb line 761
· View on GitHub
· Improve this page
· Find usages on GitHub
Defined in ActiveRecord::ConnectionAdapters::SchemaStatements