SQL
Course Process
The SQL LIKE clause is used to compare a value to similar values using wildcard operators. There are two wildcards used in conjunction with the LIKE operator.
- The percent sign (%)
- The underscore (_)
The percent sign represents zero, one or multiple characters. The underscore represents a single number or character. These symbols can be used in combinations.
Syntax
The basic syntax of % and _ is as follows −
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_'
You can combine N number of conditions using AND or OR operators. Here, XXXX could be any numeric or string value.
Example
The following table has a few examples showing the 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 have a 2 in the second position and end with a 3. |
| 7 | WHERE SALARY LIKE ‘2___3’ Finds any values in a five-digit number that start with 2 and end with 3. |
Let us take a real example, consider the CUSTOMERS table having the records as shown below.
+----+----------+-----+-----------+----------+ | ID | NAME | AGE | ADDRESS | SALARY | +----+----------+-----+-----------+----------+ | 1 | Ramesh | 32 | Ahmedabad | 2000.00 | | 2 | Khilan | 25 | Delhi | 1500.00 | | 3 | kaushik | 23 | Kota | 2000.00 | | 4 | Chaitali | 25 | Mumbai | 6500.00 | | 5 | Hardik | 27 | Bhopal | 8500.00 | | 6 | Komal | 22 | MP | 4500.00 | | 7 | Muffy | 24 | Indore | 10000.00 | +----+----------+-----+-----------+----------+
Following is an example, which would display all the records from the CUSTOMERS table, where the SALARY starts with 200.
SQL> SELECT * FROM CUSTOMERS WHERE SALARY LIKE '200%';
This would produce the following result −
+----+----------+-----+-----------+----------+ | ID | NAME | AGE | ADDRESS | SALARY | +----+----------+-----+-----------+----------+ | 1 | Ramesh | 32 | Ahmedabad | 2000.00 | | 3 | kaushik | 23 | Kota | 2000.00 | +----+----------+-----+-----------+----------+
