如何獲得行數爲

Question

列

所以我有這樣

SELECT DISTINCT colB FROM tbl WHERE colA = "foo" LIMIT 0, 20 

這讓我有最大的數組的查詢。 20條記錄，其中colA匹配"foo"，但沒有重複記錄。每個陣列條目包含一個關聯數組，其中包含的colB的價值，就像

0 => array(
     'colB' => 'some_value', 
    ), 
1 => array(
     'colB' => 'other_value', 
    ) 

我也能得到COUNT()爲colB價值？我的意思是這樣的：

SELECT COUNT() as cbCount FROM tbl WHERE colA = "foo" AND colB = "some_value" 
SELECT COUNT() as cbCount FROM tbl WHERE colA = "foo" AND colB = "other_value" 

但包含在第一查詢作爲另一個陣列領域，如：

0 => array(
     'colB' => 'some_value', 
     'cbCount' => 5, 
    ), 
1 => array(
     'colB' => 'other_value', 
     'cbCount' => 2, 
    ) 

Answer 1

您需要使用Group By與Count -

SELECT 
     colB, count(colB) as cbCount 
FROM  
     tbl 
WHERE 
     colA = 'foo' 
GROUP BY 
     colB 
LIMIT 
     0, 20 

此查詢將獲取前20行，根據不同的值colB對它們進行分組並計數。

Answer 2

所有你需要做的是使用GROUP BY條款

SELECT colB, 
     COUNT(colB) AS cbCount 
FROM tableName 
WHERE colA = 'Foo' 
GROUP BY colB