String Type

This page provides a clear explanation of the most commonly used data type, the String type. We will give some examples, including the one using the string function, which allows you to store and manage the string data.

Overview

The string data type is a UTF8 encoded string with Unicode support, which stores a sequence of characters (text).

Examples

Let’s create an employee table with a string data type in each column:

CREATE TABLE employee (
employeeName string,
employeeDept string,
employeeRole string
);

INSERT INTO  employee (employeeName, employeeDept, employeeRole)
VALUES 
    ('John','Finance','Staff'),
    ('Maya','Product','Staff'),
    ('Jane','Finance','Staff'),
    ('Phil','HR','Manager');

The created table is shown below:

+---------------+---------------+---------------+
| employeename  | employeedept  | employeerole  |
+---------------+---------------+---------------+
| John          | Finance       | Staff         |
| Maya          | Product       | Staff         |
| Jane          | Finance       | Staff         |
| Phil          | HR            | Manager       |
+---------------+---------------+---------------+

String with SUBSTR Function

The substr() function extracts a specific number of characters from a string.

Syntax

substr( string, start_position, length )

Let’s analyze the above syntax:

• string is the specified string.
• start_position is used as the starting position, specifying the part from where the substring is to be returned. It is written in an integer value.
• length is used to determine the number of characters to be extracted. It can be one or more characters.

Example

Insert value into the string column.

SELECT substr('Watermelon',6,5) AS "Fruit";

The updated table is shown below:

+-------------+
| Fruit       |
+-------------+
| melon       |
+-------------+

String with LENGTH Function

The length() function returns a number of characters in a string.

Syntax

The length function will take a string as a parameter.

LENGTH(string);

Example

Insert value into the string column.

SELECT LENGTH ('UNITED STATES');

The updated table is shown below:

+---------+
| length  |
+---------+
| 13      |
+---------+