why the database table TABLES.table_rows column does not match select count(*) from the physical table in MySQL -

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when comparing information_schema.tables.table_rows column physical row count retrieved "select count(*) " numbers not match. why row counts different?

mysql> select table_rows tables table_name = 'gbl_session' , table_schema = 'mydb'; +------------+ | table_rows | +------------+ |       7306 | +------------+ 1 row in set (0.01 sec)  mysql> select count(*) mydb.gbl_session; +----------+ | count(*) | +----------+ |     7800 | +----------+ 1 row in set (0.01 sec)

for innodb tables, row count rough estimate used in sql optimization. (this true if innodb table partitioned.)

read more information: https://dev.mysql.com/doc/refman/5.1/en/tables-table.html

as comment on there suggests, can try to:

table_rows (and perhaps other columns in information_schema.tables) may out of sync current table contents, can update running analyze.


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