Results for “data”
Small, practical examples. Search by task or narrow things down below.
Return zero for a sum over no rows
SQL: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
SQL✓ Tested
Return zero for a sum over no rows
SQL Server: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
SQL Server✓ Tested
Return zero for a sum over no rows
Postgres: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
Postgres✓ Tested
Return zero for a sum over no rows
SQLite: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
SQLite✓ Tested
Roll back a trial update
Group a change in a transaction and undo it.
transaction✓ Tested
Round a timestamp down to its month
Group dates by a calendar boundary.
date_trunc✓ Tested
Run a first SELECT query
SQL: Return a literal value without creating a table.
SQL✓ Tested
Run a first SELECT query
SQL Server: Return a literal value without creating a table.
SQL Server✓ Tested
Run with a read-only root filesystem
Add a temporary writable location while protecting the image filesystem.
read-only✓ Tested
Safely read a caught error
Check the error type before accessing its message.
unknown✓ Tested
Save and reload an image archive
Docker / Compose: save preserves image metadata and tags for later loading.
Docker / Compose✓ Tested
Search for a literal LIKE wildcard
SQL: Declare an escape character so a percent sign in the pattern is literal.
SQL✓ Tested