Results for “constraints”
Small, practical examples. Search by task or narrow things down below.
Reject duplicate business identifiers
SQLite: A UNIQUE constraint protects a business key independently of the primary key.
SQLite✓ Tested
Remove dependent rows with a declared cascade
SQL: ON DELETE CASCADE removes children when their referenced parent is deleted.
SQL✓ Tested
Remove dependent rows with a declared cascade
SQL Server: ON DELETE CASCADE removes children when their referenced parent is deleted.
SQL Server✓ Tested
Remove dependent rows with a declared cascade
Postgres: ON DELETE CASCADE removes children when their referenced parent is deleted.
Postgres✓ Tested
Remove dependent rows with a declared cascade
SQLite: ON DELETE CASCADE removes children when their referenced parent is deleted.
SQLite✓ Tested
Require a checkbox to be selected
HTML: A required checkbox is invalid until that individual control is checked.
HTML✓ Tested
Require a nonempty text value
HTML: The required attribute makes an empty text control fail native constraint validation.
HTML✓ Tested
Require a value with NOT NULL
SQL: Declare required fields at the database boundary, not only in application validation.
SQL✓ Tested
Require a value with NOT NULL
SQL Server: Declare required fields at the database boundary, not only in application validation.
SQL Server✓ Tested
Require a value with NOT NULL
Postgres: Declare required fields at the database boundary, not only in application validation.
Postgres✓ Tested
Require a value with NOT NULL
SQLite: Declare required fields at the database boundary, not only in application validation.
SQLite✓ Tested
Require numeric values on a chosen step
HTML: The step interval is measured from the minimum value when one is provided.
HTML✓ Tested