Question

我有这个查询，它从结果中提供了我之前的ID，但它包含多个where子句。

SELECT DISTINCT Contacts.cm_id 
    FROM Contacts 
    LEFT JOIN Employee ON (Contacts.cm_id = Employee.ei_contact_id) AND (Employee.ei_primary_employer = "Y") 

WHERE ( CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' 
    AND CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) NOT LIKE 'NULL' ) 

WHERE Contacts.cm_id < (
    SELECT DISTINCT Contacts.cm_id 
        FROM Contacts 
        LEFT JOIN Employee ON (Contacts.cm_id = Employee.ei_contact_id) AND (Employee.ei_primary_employer = "Y") 
        WHERE ( CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' AND CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) NOT LIKE 'NULL' ) 
        WHERE Contacts.cm_id='77')

ORDER BY Contacts.cm_id DESC LIMIT 1

它给了我error

'WHERE Contacts.cm_id='313')) ORDER BY Contact_Master.cm_id DESC LIMIT 1' at line 10

如何调整此查询以避免查询中断。请帮忙

Answer 1

您的查询语法错误，AND之后的LEFT JOIN ... ON ...应位于WHERE caluse中，并将WHERE calus与AND组合而不是每次WHERE，通常每个WHERE只有一个SELECT。

尝试这样的事情：

SELECT DISTINCT Contacts.cm_id 
FROM Contacts LEFT JOIN Employee 
     ON (Contacts.cm_id = Employee.ei_contact_id) 
WHERE (Employee.ei_primary_employer = "Y") 
  AND ( CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' 
  AND CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) NOT LIKE 'NULL' ) 
  AND Contacts.cm_id < 
     (SELECT DISTINCT Contacts.cm_id 
      FROM Contacts LEFT JOIN Employee 
           ON (Contacts.cm_id = Employee.ei_contact_id)  
      WHERE (Employee.ei_primary_employer = "Y") 
        AND (CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' 
        AND CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) NOT LIKE 'NULL' ) 
        AND Contacts.cm_id='77') ORDER BY Contacts.cm_id DESC LIMIT 1)

Answer 2

格式化查询使其可读如果在where子句中使用任何聚合函数，请使用

HAVING

Answer 3

我认为你不应该有2个'WHERE'语句。在每个陈述中将第二个'WHERE'更改为'AND'。

Answer 4

除非是另一个查询中的子查询，否则不能写多个where子句。您可以根据需要通过“AND”或“OR”而不是其他WHERE来调整查询。

尝试以下查询（我放置AND而不是WHERE，您可以根据需要调整AND。）

SELECT DISTINCT Contacts.cm_id FROM Contacts 
LEFT JOIN Employee ON (Contacts.cm_id = Employee.ei_contact_id) AND 
(Employee.ei_primary_employer = "Y") 

WHERE ( CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' AND 
CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) NOT LIKE 'NULL' ) 
AND Contacts.cm_id < (SELECT DISTINCT Contacts.cm_id FROM Contacts LEFT JOIN Employee  
ON (Contacts.cm_id = Employee.ei_contact_id) AND (Employee.ei_primary_employer = "Y") 
AND ( CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' AND  
CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) NOT LIKE 'NULL' ) 
AND Contacts.cm_id='77') 
ORDER BY Contacts.cm_id DESC LIMIT 1

* 注意：* 此查询未经过测试，仅适用于您的想法。它可能/可能不起作用。

谢谢

Answer 5

我建议您再次检查syntax of SELECT in MySQL，因为您的查询完全错误。

由于我不知道您想要检索的数据库结构和原始任务，我不确定结果是否正确。

但是在你的查询中摆脱了过度，我得到了这个：

SELECT MAX Contacts.cm_id as cm_id FROM Contacts LEFT JOIN Employee ON (Contacts.cm_id = Employee.ei_contact_id) WHERE Employee.ei_primary_employer = "Y" AND CONCAT( Contacts.cm_fname," ", Contacts.cm_lname ) LIKE '%Recee Dawn%' AND Contacts.cm_id < 77

希望你能得到你所期望的。

如何在单个查询中调整多个'where'子句？

5 个答案: