Invalid explicit locking with aggregate functions

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Goal This query identifies SQL statements that attempt to apply explicit row locking (e.g., FOR SHARE, FOR UPDATE) to the result of an aggregate function (e.g., COUNT(*)). This is a semantic error because locking clauses operate on specific physical rows, whereas aggregate functions return a derived scalar value that is decoupled from the underlying row versions. To correctly enforce a lock, the query must select the specific columns (typically the primary key) of the target rows, rather than a computed aggregate.
Notes Refers to the column pg_proc.prokind and thus works starting from PostgreSQL 11. In the returned body of routine the query replaces each newline character with the line break (br) tag for the better readability in case the query result is displayed in a web browser. There could be multiple routines with the same name but with different parameters in the same schema (overloading). Thus, for the unique identification of the routine it is necessary to present also its parameters in addition to the schema name and routine name.
Type Problem detection (Each row in the result could represent a flaw in the design)
Reliability Medium (Medium number of false-positive results)
License MIT License
Fixing Suggestion You must lock the specific rows that you are interested in. You should write SELECT id ... FOR SHARE.
Data Source INFORMATION_SCHEMA+system catalog
SQL Query 
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:]](count|sum|min|max|avg|string_agg)[(][^)]+[)][^;]+for[[:space:]]+(update|no[[:space:]]+key[[:space:]]+update|share|key[[:space:]]+share)' 
ORDER BY routine_schema, routine_name, parameters;
Collections

This query belongs to the following collections:

NameDescription
Find problems automaticallyQueries, 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:

NameDescription
Concurrency controlQueries of this category provide information about concurrency control.
Does not work in some earlier PostgreSQL versionQueries of this category provide information that was not available in some earlier PostgreSQL version
TransactionsQueries of this catergory provide information about the use of transactions.
User-defined routinesQueries of this category provide information about the user-defined routines