Results for “missing data”
Small, practical examples. Search by task or narrow things down below.
Treat an empty trimmed value as missing
Postgres: NULLIF converts an empty string to NULL before a fallback is applied.
Postgres✓ Tested
Treat an empty trimmed value as missing
SQLite: NULLIF converts an empty string to NULL before a fallback is applied.
SQLite✓ Tested
Insert only keys absent from a destination
SQL: NOT EXISTS supports a set-based missing-row insert in a single-writer example.
SQL✓ Tested
Insert only keys absent from a destination
SQL Server: NOT EXISTS supports a set-based missing-row insert in a single-writer example.
SQL Server✓ Tested
Insert only keys absent from a destination
Postgres: NOT EXISTS supports a set-based missing-row insert in a single-writer example.
Postgres✓ Tested
Insert only keys absent from a destination
SQLite: NOT EXISTS supports a set-based missing-row insert in a single-writer example.
SQLite✓ Tested
Keep unmatched rows with LEFT JOIN
Show every product even when stock is missing.
LEFT JOIN✓ Tested
Calculate a total for each group
SQL: Group nonmissing categories and calculate separate totals.
SQL✓ Tested
Calculate a total for each group
SQL Server: Group nonmissing categories and calculate separate totals.
SQL Server✓ Tested
Delete one matching row
Remove a selected record and inspect what remains.
DELETE✓ Tested
Read a nested optional value
Avoid dereferencing a missing nested object.
optional chaining✓ Tested
Replace NULL in a result
Choose a fallback for a missing value.
COALESCE✓ Tested