Sqlite 简明教程

SQLite - LIKE Clause

SQLite LIKE 运算符用于使用通配符将文本值与模式进行匹配。如果搜索表达式可以与模式表达式匹配，则 LIKE 运算符将返回 true，即 1。有两个通配符与 LIKE 运算符结合使用 −

SQLite LIKE operator is used to match text values against a pattern using wildcards. If the search expression can be matched to the pattern expression, the LIKE operator will return true, which is 1. There are two wildcards used in conjunction with the LIKE operator −

The percent sign (%)
The underscore (_)

百分号表示零、一或多个数字或字符。下划线表示一个数字或字符。这些符号可以结合使用。

The percent sign represents zero, one, or multiple numbers or characters. The underscore represents a single number or character. These symbols can be used in combinations.

Syntax

以下是 % 和 _ 的基本语法。

Following is the basic syntax of % and _.

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_'

你可以使用 AND 或 OR 运算符结合 N 个条件。此处，XXXX 可以是任何数字或字符串值。

You can combine N number of conditions using AND or OR operators. Here, XXXX could be any numeric or string value.

Example

下表列出了一些示例，展示了具有不同 LIKE 子句和 '%' 和 '_' 运算符的 WHERE 部分。

Following table lists a number of examples showing WHERE part having different LIKE clause with '%' and '_' operators.

Sr.No.	Statement & Description
1	WHERE SALARY LIKE '200%' Finds any values that start with 200
2	WHERE SALARY LIKE '%200%' Finds any values that have 200 in any position
3	WHERE SALARY LIKE '_00%' Finds any values that have 00 in the second and third positions
4	WHERE SALARY LIKE '2_%_%' Finds any values that start with 2 and are at least 3 characters in length
5	WHERE SALARY LIKE '%2' Finds any values that end with 2
6	WHERE SALARY LIKE '_2%3' Finds any values that has a 2 in the second position and ends with a 3
7	WHERE SALARY LIKE '2___3' Finds any values in a five-digit number that starts with 2 and ends with 3

我们来举一个实际的例子，考虑带有以下记录的 COMPANY 表。

Let us take a real example, consider COMPANY table with the following records.

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

以下是一个示例，它将显示 COMPANY 表中所有 AGE 以 2 开头的记录。

Following is an example, which will display all the records from COMPANY table where AGE starts with 2.

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

这将产生以下结果。

This will produce the following result.

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

以下是一个示例，它将显示 COMPANY 表中所有在文本中带连字符 (-) 的 ADDRESS 的记录。

Following is an example, which will display all the records from COMPANY table where ADDRESS will have a hyphen (-) inside the text.

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

这将产生以下结果。

This will produce the following result.

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