Results for “SQL”
Small, practical examples. Search by task or narrow things down below.
Update rows selected by a related table
SQLite: Use EXISTS to limit updates based on an independent eligibility table.
SQLite✓ Tested
Update several classifications in one statement
SQL: A CASE expression computes the new value for each row covered by the update predicate.
SQL✓ Tested
Update several classifications in one statement
SQL Server: A CASE expression computes the new value for each row covered by the update predicate.
SQL Server✓ Tested
Update several classifications in one statement
SQLite: A CASE expression computes the new value for each row covered by the update predicate.
SQLite✓ Tested
Accept either of two conditions
Postgres: Use OR to keep matching names or out-of-stock rows.
Postgres✓ Tested
Add an interval to a date
Perform calendar arithmetic with an interval literal.
INTERVAL✓ Tested
Add an optional field to an existing table
Postgres: A nullable column permits existing rows to remain valid while data is filled later.
Postgres✓ Tested
Add days to a date
Use DATEADD for date arithmetic.
DATEADD✓ Tested
Add days to a date
Use a date modifier for calendar arithmetic.
date✓ Tested
Add values across several rows
Postgres: Use SUM to calculate a total quantity.
Postgres✓ Tested
Apply a default when an insert omits a column
Postgres: A default supplies an omitted value; an explicit NULL still follows the column’s nullability rules.
Postgres✓ Tested
Assign a rank within each group
Number rows with a partitioned window.
ROW_NUMBER✓ Tested