The properties of MySQL query plans are defined together with operations. Please refer to the MySQL operation page for more details.
| Property | Category | Reference | Description |
|---|---|---|---|
| access_type | Link | The operation of how to read a table. We map it into an operation. | |
| attached_condition | Configuration | Link | The condition to filter out data. |
| cacheable | Status | Link | Whether the result is cacheable. |
| cost_info | Cost | Link | Estimated cost. |
| data_read_per_join | Cardinality | Link | Estimated number of rows read per join. |
| dependent | Status | Link | Whether the operation depends on another operation. |
| eval_cost | Cost | Link | Estimated cost of evaluating an expression or function. |
| filtered | Status | Link | How much percentage of rows filtered out. |
| key | Status | Link | The indexes used. |
| key_length | Status | Link | The length of indexes. |
| possible_keys | Status | Link | The possible indexes in the accessed tables. |
| prefix_cost | Cost | Link | Estimated cost to join data. |
| query_cost | Cost | Link | Estimated cost of querying. |
| read_cost | Cost | Link | Estimated cost to read data. |
| ref | Configuration | Link | The columns that are compared with the used indexes. |
| rows_examined_per_scan | Cardinality | Link | Estimated number of rows read. |
| rows_produced_per_join | Cardinality | Link | Estimated number of rows returned. |
| sort_cost | Cost | Link | Estimated cost of sorting. |
| table_name | Configuration | Link | The name of the accessed table. |
| used_columns | Status | Link | The columns used in this operation. |
| used_key_parts | Status | Link | The used keys. |
| using_filesort | Status | Link | Whether uses the filesort. |
| using_temporary_table | Status | Link | Whether the table is temp. |