Results for “Relationships & missing data”
Small, practical examples. Search by task or narrow things down below.
Include zero counts for missing relationships
SQL: Count the non-null child key after a left join so a missing relationship produces zero.
SQL✓ Tested
Include zero counts for missing relationships
SQL Server: Count the non-null child key after a left join so a missing relationship produces zero.
SQL Server✓ Tested
Include zero counts for missing relationships
Postgres: Count the non-null child key after a left join so a missing relationship produces zero.
Postgres✓ Tested
Include zero counts for missing relationships
SQLite: Count the non-null child key after a left join so a missing relationship produces zero.
SQLite✓ Tested
Find parents whose every child meets a rule
SQL: Combine existence with the absence of a violating child to exclude parents with no children.
SQL✓ Tested
Find parents whose every child meets a rule
SQL Server: Combine existence with the absence of a violating child to exclude parents with no children.
SQL Server✓ Tested
Find parents whose every child meets a rule
Postgres: Combine existence with the absence of a violating child to exclude parents with no children.
Postgres✓ Tested
Find parents whose every child meets a rule
SQLite: Combine existence with the absence of a violating child to exclude parents with no children.
SQLite✓ Tested
Find parents with at least two child rows
SQL: Use a correlated count when testing a per-parent threshold.
SQL✓ Tested
Find parents with at least two child rows
SQL Server: Use a correlated count when testing a per-parent threshold.
SQL Server✓ Tested
Find parents with at least two child rows
Postgres: Use a correlated count when testing a per-parent threshold.
Postgres✓ Tested
Find parents with at least two child rows
SQLite: Use a correlated count when testing a per-parent threshold.
SQLite✓ Tested