This query identifies SQL routines that utilize explicit row locking clauses (e.g., FOR UPDATE, FOR SHARE) in queries that do not target a specific base table or relation. For instance, a statement like SELECT 'text' AS v FOR UPDATE attempts to apply a lock to a scalar constant. Since row-level locks in PostgreSQL require a physical row version (tuple) within a table to be effective, such statements are semantically void. They indicate a fundamental misunderstanding of the concurrency control mechanism and should be corrected to target actual table rows.
Type
Problem detection (Each row in the result could represent a flaw in the design)
SELECT
pg_namespace.nspname AS routine_schema,
pg_proc.proname AS routine_name,
pg_get_function_identity_arguments(pg_proc.oid) AS parameters,
CASE WHEN pg_proc.prokind='f' THEN 'FUNCTION'
WHEN pg_proc.prokind='p' THEN 'PROCEDURE'
WHEN pg_proc.prokind='w' THEN 'WINDOW FUNCTION' END AS routine_type,
regexp_replace( regexp_replace(pg_get_functiondef(pg_proc.oid),'<','<','g'),'[\r\n]',' ','g') AS routine_src
FROM
pg_catalog.pg_proc,
pg_catalog.pg_namespace
WHERE
pg_proc.pronamespace = pg_namespace.oid
AND pg_proc.prokind<>'a'
AND pg_proc.proname NOT IN ('f_assume_you_must_use_files', 'f_check_format_comma_separated_list', 'f_check_password', 'f_default_value_with_no_match')
AND pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL)
AND pg_get_functiondef(pg_proc.oid)~*'[[:space:]]select[[:space:]][^;]*(?
SQL statements that help generate fixes for the identified problem.
SQL Query to Generate Fix
Description
WITH unnecessary_for_update AS (SELECT
pg_namespace.nspname AS routine_schema,
pg_proc.proname AS routine_name,
pg_get_function_identity_arguments(pg_proc.oid) AS parameters
FROM
pg_catalog.pg_proc,
pg_catalog.pg_namespace
WHERE
pg_proc.pronamespace = pg_namespace.oid
AND pg_proc.prokind<>'a'
AND pg_proc.proname NOT IN ('f_assume_you_must_use_files', 'f_check_format_comma_separated_list', 'f_check_password', 'f_default_value_with_no_match')
AND pg_namespace.nspname NOT IN (SELECT schema_name
FROM INFORMATION_SCHEMA.schemata
WHERE schema_name<>'public' AND
schema_owner='postgres' AND schema_name IS NOT NULL)
AND pg_get_functiondef(pg_proc.oid)~*'[[:space:]]select[[:space:]][^;]*(?
Drop the routine.
Collections
This query belongs to the following collections:
Name
Description
Find problems automatically
Queries, that results point to problems in the database. Each query in the collection produces an initial assessment. However, a human reviewer has the final say as to whether there is a problem or not .
Categories
This query is classified under the following categories:
Name
Description
Concurrency control
Queries of this category provide information about concurrency control.
Does not work in some earlier PostgreSQL version
Queries of this category provide information that was not available in some earlier PostgreSQL version
User-defined routines
Queries of this category provide information about the user-defined routines