Optimizer Configuration Metrics
Lists the Optimizer configuration metrics and provides a brief description of each.
| Name | Description |
|---|---|
| End Markers In Json Enabled | Whether optimizer JSON output adds end markers. |
| Eq Range Index Dive Limit | Indicates the number of equality ranges in an equality comparison condition when the optimizer switches from using index dives to index statistics in estimating the number of qualifying rows. |
| Histogram Generation Max Mem Size | The maximum amount of memory available for generating histogram statistics. |
| Max Length For Sort Data | The maximum size of parameter values that can be sent with the mysql_stmt_send_long_data() C API function. |
| Max Seeks For Key | Limit the assumed maximum number of seeks when looking up rows based on a key. |
| Max Sort Length | The number of bytes to use when sorting data values. Only the first max_sort_length bytes of each value are used; the rest are ignored. |
| Prune Level Enabled | Controls the heuristics applied during query optimization to prune less- promising partial plans from the optimizer search space. |
| Range Alloc Block Size | The size of blocks (in bytes) that are allocated when doing range optimization. |
| Search Depth | The maximum depth of search performed by the query optimizer. |
| Switch Value | The optimizer_switch system variable enables control over optimizer behavior. |
| Trace | Controls how to enable optimizer tracing. |
| Trace Features | Enables or disables selected optimizer tracing features. |
| Trace Limit | The maximum cumulative size of stored optimizer traces. |
| Trace Max Mem Size | The maximum cumulative size of stored optimizer traces. |
| Trace Offset | The offset of optimizer traces to display. |
| Windowing Use High Precision Enabled | Whether to compute window operations without loss of precision. Default is ON. |