### Values Scan ![[assets/ex_values_scan.png|256]] ### The Explain Trace ```sql -- Scanning a literal list of tuples EXPLAIN (ANALYZE, COSTS, BUFFERS, VERBOSE) VALUES (1, 'a'), (2, 'b'); ``` ```text Values Scan on "*VALUES*" (cost=1.00..1.03 rows=2 width=36) (actual time=1.007..1.008 rows=2 loops=1) Output: column1, column2 ``` --- - **Description**: Scans a list of constant values. - **Performance**: High performance; the tuples are typically stored directly in the query plan and do not require heap access. - **Factors**: The number of values provided in the clause. - **Cost**: `cpu_tuple_cost * number of values` - **Operates on**: [[Structures/Tuple]] - **Workloads**: - [[Workloads/LWLock/Buffers/BufferContent|LWLock: BufferContent]]