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SQLite LIKE 子句

SQLite的LIKE操作符是用來反對使用通配符的模式匹配的文本值。如果搜索表達式可以匹配的圖案表達,LIKE運算將返回true,也就是1。有兩個通配符與LIKE運算符一起使用:

  • 百分號 (%)

  • 下劃線 (_)

百分號表示零個,一個或多個數字或字符。下劃線代表一個單一的數字或字符。這些符號可以被組合使用。

語法

%和_的基本語法如下:

SELECT FROM table_name
WHERE column LIKE 'XXXX%'

or 

SELECT FROM table_name
WHERE column LIKE '%XXXX%'

or

SELECT FROM table_name
WHERE column LIKE 'XXXX_'

or

SELECT FROM table_name
WHERE column LIKE '_XXXX'

or

SELECT FROM table_name
WHERE column LIKE '_XXXX_'

可以結合的條件下使用AND或OR運算的N多。XXXX在這裡可以是任何數字或字符串值。

例子:

下麵一些例子顯示LIKE子句以'%'和'_'運算符具有不同的部分:

語句 描述
WHERE SALARY LIKE '200%' Finds any values that start with 200
WHERE SALARY LIKE '%200%' Finds any values that have 200 in any position
WHERE SALARY LIKE '_00%' Finds any values that have 00 in the second and third positions
WHERE SALARY LIKE '2_%_%' Finds any values that start with 2 and are at least 3 characters in length
WHERE SALARY LIKE '%2' Finds any values that end with 2
WHERE SALARY LIKE '_2%3' Finds any values that have a 2 in the second position and end with a 3
WHERE SALARY LIKE '2___3' Finds any values in a five-digit number that start with 2 and end with 3

讓我們舉一個實際的例子,考慮COMPANY表有以下記錄:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          California  20000.0
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0
7           James       24          Houston     10000.0

以下是一個例子,它會從公司表顯示年齡以2開頭 的所有記錄:

sqlite> SELECT * FROM COMPANY WHERE AGE  LIKE '2%';

這將產生以下結果:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0
7           James       24          Houston     10000.0

以下是一個例子,它會顯示所有記錄從公司表的地址將有一個連字符( - ),裡麵的文字:

sqlite> SELECT * FROM COMPANY WHERE ADDRESS  LIKE '%-%';

這將產生以下結果:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
4           Mark        25          Rich-Mond   65000.0
6           Kim         22          South-Hall  45000.0