行数是InnoDB用于查询优化的近似值.进行count(*)效率低得多，对行数有一个大概的了解就足以优化查询计划. phpMyAdmin将执行显示表状态"查询以获取有关表的信息:

The row count is an approximation used for query optimisation by InnoDB. doing a count(*) is a lot more inefficient and having a rough idea of the number of rows is sufficient to optimise the query plan. phpMyAdmin will be doing a "show table status" query to get the information about the table:

http://dev.mysql.com/doc/refman/5.0 /en/show-table-status.html

对于其他存储引擎，例如InnoDB，此值为 近似值，可能与实际值相差40到 50％.在这种情况下，请使用SELECT COUNT(*)获得准确的计数.

For other storage engines, such as InnoDB, this value is an approximation, and may vary from the actual value by as much as 40 to 50%. In such cases, use SELECT COUNT(*) to obtain an accurate count.