Results for “SQL”
Small, practical examples. Search by task or narrow things down below.
Sort the highest quantities first
Postgres: Specify descending order and a stable tie breaker.
Postgres✓ Tested
Split delimited text with positions
Retain original order with STRING_SPLIT ordinals.
STRING_SPLIT✓ Tested
Substitute a value for NULL
Use SQL Server’s ISNULL expression.
ISNULL✓ Tested
Sum a row and its immediate predecessor
Postgres: A ROWS frame counts physical ordered rows rather than all peers with the same sort value.
Postgres✓ Tested
Sum values per category
Calculate a grouped total.
SUM✓ Tested
Test missing values with IS NULL
Find rows where an optional value is absent.
IS NULL✓ Tested
Treat an empty trimmed value as missing
Postgres: NULLIF converts an empty string to NULL before a fallback is applied.
Postgres✓ Tested
Turn a condition into a result label
Postgres: Use CASE to describe stock availability for each row.
Postgres✓ Tested
Turn JSON into typed rows
Project JSON array items into SQL columns.
OPENJSON✓ Tested
Turn known group values into columns
Postgres: Conditional aggregation gives a portable pivot when the category set is known.
Postgres✓ Tested
Undo a multi-row transfer atomically
Postgres: The first transaction commits the fixtures. Rolling back the second transaction restores both sides of the attempted transfer.
Postgres✓ Tested
Undo only the work after a savepoint
Postgres: After committing the fixtures, roll back a trial change while keeping earlier work in the second transaction.
Postgres✓ Tested