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mysql select count(*) from main_index; 但是这个在这里却报语法错误 第一种方法 查文档得 Aggregate functions (AVG() MIN() MAX() SUM()) in column list clause are supported Arguments to aggregate functions can be either plain attributes or arbitrary expressions COUNT(*) is implicitly supported as using GROUP BY will add @count column to result set Explicit support might be added in the future COUNT(DISTINCT attr) is supported Currently there can be at most one COUNT(DISTINCT) per query and an argument needs to be an attribute Both current restrictions on COUNT(DISTINCT) might be lifted in the future 也就是说只有在group by的时候才能用count(*)如 复制代码 代码如下: select as dummycount(*) c from main_index group by dummy; +++++ | id | weight | dummy | @count | +++++ | | | | | +++++ 第二种方法 复制代码 代码如下: select * from main_index limit ; show meta; +++ | Variable_name | Value | +++ | total | | | total_found | | | time | | | keyword[] | ha | | docs[] | | | hits[] | | +++ 也就是说用show meta来得到这个total_found这个就是总记录数 下面我们来说一下show meta: SHOW META shows additional metainformation about the latest query such as query time and keyword statistics: 也就是说它显示的是最近一次查询附加的一些信息比如查询时间关键字统计总记录等 复制代码 代码如下: mysql> SELECT * FROM test WHERE MATCH(test|one|two); +++++ | id | weight | group_id | date_added | +++++ | | | | | | | | | | | | | | | +++++ rows in set ( sec) mysql> SHOW META; +++ | Variable_name | Value | +++ | total | | | total_found | | | time | | | keyword[] | test | | docs[] | | | hits[] | | | keyword[] | one | | docs[] | | | hits[] | | | keyword[] | two | | docs[] | | | hits[] | | +++ rows in set ( sec) 在PHP中如何调用？ 复制代码 代码如下: <?php //获取总记录个数 private function getTotalFound($conn) { $sql = show meta; $total_result = @mysql_query ( $sql$conn ); $totals = array (); while ( ($row = mysql_fetch_assoc ( $total_result )) !== false ) { $totals [$row [Variable_name]] = $row [Value]; } return $totals; } ?> 注意如果代码中用了多个数据库连接的话这个相应的conn必须传进来否则是取不到结果的 |
