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uses existing index statistics instead of index dives if there are eq_range_index_dive_limit or more equality ranges. Thus, to permit use of index dives for up to N  equality ranges, set eq_range_index_dive_limit  to N  + 1. To disable use of index statistics and always use index dives regardless of N , set eq_range_index_dive_limit  to 0. 

For more information, see Equality Range Optimization of Many-Valued Comparisons. 

To update table index statistics for best estimates, use ANALYZE TABLE . 

• error_count 

The number of errors that resulted from the last statement that generated messages. This variable is read only. See Section 13.7.7.17, “SHOW ERRORS Statement” . 

• event_scheduler 

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This variable enables or disables, and starts or stops, the Event Scheduler. The possible status values are ON , OFF , and DISABLED , with the default being OFF . Turning the Event Scheduler OFF  is not the same as disabling the Event Scheduler, which requires setting the status to DISABLED . This variable and its effects on the Event Scheduler’s operation are discussed in greater detail in Section 25.4.2, “Event Scheduler Configuration” 

• explicit_defaults_for_timestamp 

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This system variable determines whether the server enables certain nonstandard behaviors for default values and NULL -value handling in TIMESTAMP  columns. By default, 

