我有 MySQL 查询
SELECT count( * ) AS total
FROM `orders` o, `orders_status` s, `orders_status_history` osh
LEFT JOIN `orders_total` ot ON ot.orders_id = o.orders_id
WHERE o.orders_status = s.orders_status_id
AND osh.orders_id = o.orders_id
AND s.language_id = '5'
AND s.orders_status_id = '6'
AND ot.class = 'ot_total'
收到此错误:
#1054 - Unknown column 'o.orders_id' in 'on clause'
我的表架构如下:
CREATE TABLE IF NOT EXISTS `orders` (
`orders_id` int(11) NOT NULL auto_increment,
`customers_id` int(11) NOT NULL default '0',
`last_modified` datetime default NULL,
`orders_status` int(5) NOT NULL default '0',
`orders_date_finished` datetime default NULL,
`comments` text,
`currency` char(3) default NULL,
`currency_value` decimal(14,6) default NULL,
`invoice_number` varchar(100) default NULL,
PRIMARY KEY (`orders_id`)
) ENGINE=MyISAM DEFAULT CHARSET=cp1251 AUTO_INCREMENT=8419 ;
我无法理解错误的来源。有什么想法吗?
答案 0 :(得分:2)
您的订单表的表别名为OR
。您需要更改表别名。
SELECT count( * ) AS total
FROM `orders` o , `orders_status` s, `orders_status_history` osh
LEFT JOIN `orders_total` ot ON ot.orders_id = or.orders_id
WHERE o.orders_status = s.orders_status_id
AND osh.orders_id = or.orders_id
AND s.language_id = '5'
AND s.orders_status_id = '6'
AND ot.class = 'ot_total'
您还应该更改JOIN语法
SELECT count( * ) AS total
FROM `orders` o
LEFT JOIN `orders_status` s
ON o.order_status = s.orders_status_id
LEFT JOIN `orders_status_history` osh
ON osh.orders_id = o.orders_id
LEFT JOIN `orders_total` ot
ON ot.orders_id = o.orders_id
WHERE s.language_id = '5'
AND s.orders_status_id = '6'
AND ot.class = 'ot_total'
答案 1 :(得分:2)
如the manual中所述:
以前,逗号运算符(
,
)和JOIN
都具有相同的优先级,因此连接表达式t1, t2 JOIN t3
被解释为((t1, t2) JOIN t3)
。现在JOIN
具有更高的优先级,因此表达式被解释为(t1, (t2 JOIN t3))
。此更改会影响使用ON
子句的语句,因为该子句只能引用连接操作数中的列,并且优先级的更改会更改这些操作数的解释。示例:
CREATE TABLE t1 (i1 INT, j1 INT); CREATE TABLE t2 (i2 INT, j2 INT); CREATE TABLE t3 (i3 INT, j3 INT); INSERT INTO t1 VALUES(1,1); INSERT INTO t2 VALUES(1,1); INSERT INTO t3 VALUES(1,1); SELECT * FROM t1, t2 JOIN t3 ON (t1.i1 = t3.i3);
以前,
SELECT
是合法的,因为t1,t2
隐式分组为(t1,t2)
。现在JOIN
优先,因此ON
子句的操作数为t2
和t3
。由于t1.i1
不是任一操作数中的列,因此结果为Unknown column 't1.i1' in 'on clause'
错误。要允许处理连接,请使用括号将前两个表显式分组,以便ON
子句的操作数为(t1,t2)
和t3
:SELECT * FROM (t1, t2) JOIN t3 ON (t1.i1 = t3.i3);
或者,避免使用逗号运算符并改为使用
JOIN
:SELECT * FROM t1 JOIN t2 JOIN t3 ON (t1.i1 = t3.i3);
此更改也适用于将逗号运算符与
INNER JOIN
,CROSS JOIN
,LEFT JOIN
和RIGHT JOIN
混合在一起的语句,所有这些语句现在都具有比逗号更高的优先级操作
答案 2 :(得分:1)
或者是一个mysql关键字!用其他东西替换它,例如_or&再试一次!