T-SQL LEFT() Function
The T-SQL (Transact-SQL) LEFT() function is used to extract a substring from a string, starting from the left-most character.
Syntax
LEFT(string, number_of_chars)
Parameters
string |
Required. Specify the string to extract from. |
number_of_chars |
Required. Specify the number of characters to extract. If this parameter exceeds the length of the string, this function will return string. |
Return Value
Returns the substring extracted from specified string.
Example 1:
The example below shows the usage of LEFT() function.
SELECT LEFT('AlphaCodingSkills.com', 1);
Result: 'A'
SELECT LEFT('AlphaCodingSkills.com', 5);
Result: 'Alpha'
SELECT LEFT('AlphaCodingSkills.com', 21);
Result: 'AlphaCodingSkills.com'
SELECT LEFT('AlphaCodingSkills.com', 50);
Result: 'AlphaCodingSkills.com'
SELECT LEFT('Alpha Coding Skills', 5);
Result: 'Alpha'
Example 2:
Consider a database table called Employee with the following records:
| PhoneNumber | EmpID | Address |
|---|---|---|
| +33-147996101 | 1 | Grenelle, Paris, France |
| +31-201150319 | 2 | Geuzenveld, Amsterdam, Netherlands |
| +86-1099732458 | 3 | Yizhuangzhen, Beijing, China |
| +65-67234824 | 4 | Yishun, Singapore |
| +81-357799072 | 5 | Koto City, Tokyo, Japan |
In the query below, the LEFT() function is used to extract the country code from the PhoneNumber column records.
SELECT *, LEFT(PhoneNumber, 3) AS CountryCode FROM Employee;
This will produce the result as shown below:
| PhoneNumber | EmpID | Address | CountryCode |
|---|---|---|---|
| +33-147996101 | 1 | Grenelle, Paris, France | +33 |
| +31-201150319 | 2 | Geuzenveld, Amsterdam, Netherlands | +31 |
| +86-1099732458 | 3 | Yizhuangzhen, Beijing, China | +86 |
| +65-67234824 | 4 | Yishun, Singapore | +65 |
| +81-357799072 | 5 | Koto City, Tokyo, Japan | +81 |
❮ T-SQL Functions
