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Measures reported by MySQLTabScanTest
Full table scans on a database instance can degrade the performance of the database. This test monitors the extent of full table scans happening on the database.
Outputs of the test : One set of results for the target MySQL database server being monitored
The measures made by this test are as follows:
| Measurement |
Description |
Measurement Unit |
Interpretation |
| FullTableScans |
Indicates the number of full table scans that happened on the database during the last measurement period. |
Number |
This type of scan reads all rows from a table and filters out those that do not meet the selection criteria. Full table scans may happen due to several reasons. For instance, the indexes of a table may not be used properly in queries. By tuning the queries, the full table scans can be reduced and the database performance significantly improved. |
| MaxRowExamined |
Indicates the maximum number of rows examined during the last measurement period. |
Seconds |
The detailed diagnosis of this measure lists the Thread ID, Statement ID, Schema name, Query duration, Table lock wait time (Seconds), Temp disk tables created, Temp tables created, Rows sent, Rows examined, |
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