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why not use JOIN statement for joining tables? (vol. 2)

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This commit is contained in:
Akira Matsuda
2011-05-18 18:31:34 +09:00
parent df13f55d75
commit 486a890505
1 changed files with 12 additions and 21 deletions
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33
activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
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@@ -820,18 +820,13 @@ module ActiveRecord
# given table's primary key.
result = exec_query(<<-end_sql, 'SCHEMA').rows.first
SELECT attr.attname, seq.relname
FROM pg_class seq,
pg_attribute attr,
pg_depend dep,
pg_constraint cons
WHERE seq.oid = dep.objid
AND seq.relkind = 'S'
AND attr.attrelid = dep.refobjid
AND attr.attnum = dep.refobjsubid
AND attr.attrelid = cons.conrelid
AND attr.attnum = cons.conkey[1]
AND cons.contype = 'p'
AND dep.refobjid = '#{quote_table_name(table)}'::regclass
FROM pg_class seq
INNER JOIN pg_depend dep on seq.oid = dep.objid
INNER JOIN pg_attribute attr ON attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid
INNER JOIN pg_constraint cons ON attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1]
WHERE seq.relkind = 'S'
AND cons.contype = 'p'
AND dep.refobjid = '#{quote_table_name(table)}'::regclass
end_sql
# [primary_key, sequence]
@@ -844,15 +839,11 @@ module ActiveRecord
def primary_key(table)
row = exec_query(<<-end_sql, 'SCHEMA', [[nil, table]]).rows.first
SELECT DISTINCT(attr.attname)
FROM pg_attribute attr,
pg_depend dep,
pg_constraint cons
WHERE attr.attrelid = dep.refobjid
AND attr.attnum = dep.refobjsubid
AND attr.attrelid = cons.conrelid
AND attr.attnum = cons.conkey[1]
AND cons.contype = 'p'
AND dep.refobjid = $1::regclass
FROM pg_attribute attr
INNER JOIN pg_depend dep ON attr.attrelid = dep.refobjid AND attr.attnum = dep.refobjsubid
INNER JOIN pg_constraint cons ON attr.attrelid = cons.conrelid AND attr.attnum = cons.conkey[1]
WHERE cons.contype = 'p'
AND dep.refobjid = $1::regclass
end_sql
row && row.first