Results for “subquery”
Small, practical examples. Search by task or narrow things down below.
Compare with a calculated value
Find products above the average price.
subquery✓ Tested
Find rows with a related record
Use EXISTS without duplicating the outer rows.
EXISTS✓ Tested
Attach an overall count to every row
SQL: An uncorrelated scalar subquery supplies the same aggregate to each output row.
SQL✓ Tested
Attach an overall count to every row
SQL Server: An uncorrelated scalar subquery supplies the same aggregate to each output row.
SQL Server✓ Tested
Attach an overall count to every row
Postgres: An uncorrelated scalar subquery supplies the same aggregate to each output row.
Postgres✓ Tested
Attach an overall count to every row
SQLite: An uncorrelated scalar subquery supplies the same aggregate to each output row.
SQLite✓ Tested
Build a JSON array from rows
Aggregate ordered text values into JSON.
json_group_array✓ Tested
Find records without any related rows
SQL: NOT EXISTS avoids the NULL pitfalls of NOT IN when the subquery column can be missing.
SQL✓ Tested
Find records without any related rows
SQL Server: NOT EXISTS avoids the NULL pitfalls of NOT IN when the subquery column can be missing.
SQL Server✓ Tested
Find records without any related rows
Postgres: NOT EXISTS avoids the NULL pitfalls of NOT IN when the subquery column can be missing.
Postgres✓ Tested
Find records without any related rows
SQLite: NOT EXISTS avoids the NULL pitfalls of NOT IN when the subquery column can be missing.
SQLite✓ Tested
Match one of several values
Use IN to avoid repeating equality conditions.
IN✓ Tested