primary_key(table) — ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements

primary_key(table)

Returns just a table’s primary key

Parameters

table req

Source

# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 399
        def primary_key(table)
          pks = exec_query(<<-end_sql, 'SCHEMA').rows
            SELECT attr.attname
            FROM pg_attribute attr
            INNER JOIN pg_constraint cons ON attr.attrelid = cons.conrelid AND attr.attnum = any(cons.conkey)
            WHERE cons.contype = 'p'
              AND cons.conrelid = '#{quote_table_name(table)}'::regclass
          end_sql
          return nil unless pks.count == 1
          pks[0][0]
        end

Defined in activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb line 399 · View on GitHub · Improve this page · Find usages on GitHub

Defined in ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements

Signature

Parameters