Results for “Schema design & transactions”
Small, practical examples. Search by task or narrow things down below.
Read a page after a known unique key
SQLite: A keyset predicate avoids scanning and discarding an increasing offset on a suitable index.
SQLite✓ Tested
Read named columns from a table
Postgres: Choose the columns needed and request a deterministic row order.
Postgres✓ Tested
Read the last value of the complete partition
SQL: Specify an unbounded-following frame so LAST_VALUE does not stop at the current row.
SQL✓ Tested
Read the last value of the complete partition
SQL Server: Specify an unbounded-following frame so LAST_VALUE does not stop at the current row.
SQL Server✓ Tested
Read the last value of the complete partition
Postgres: Specify an unbounded-following frame so LAST_VALUE does not stop at the current row.
Postgres✓ Tested
Read the last value of the complete partition
SQLite: Specify an unbounded-following frame so LAST_VALUE does not stop at the current row.
SQLite✓ Tested
Read the next row’s value
SQL: LEAD reads a later ordered row without a self join and supports a fallback at the end.
SQL✓ Tested
Read the next row’s value
SQL Server: LEAD reads a later ordered row without a self join and supports a fallback at the end.
SQL Server✓ Tested
Read the next row’s value
Postgres: LEAD reads a later ordered row without a self join and supports a fallback at the end.
Postgres✓ Tested
Read the next row’s value
SQLite: LEAD reads a later ordered row without a self join and supports a fallback at the end.
SQLite✓ Tested
Read the smallest and largest values
Postgres: Use MIN and MAX without sorting and fetching every row.
Postgres✓ Tested
Reference a parent identified by two columns
SQL: A composite foreign key checks the complete referenced key rather than either column independently.
SQL✓ Tested