MySQL LCASE() String Function

MySQL LCASE() String Function

The MySQL LCASE() string function converts all characters in a string to lowercase. This function is essential for standardizing the case of strings in SQL queries.

Syntax

SELECT LCASE(string) AS result
FROM table_name;

The LCASE() function has the following components:

  • string: The string to be converted to lowercase.
  • result: An alias for the resulting lowercase string.
  • table_name: The name of the table from which to retrieve the data.

Example MySQL LCASE() String Function

Let's look at some examples of the MySQL LCASE() string function:

Step 1: Using the Database

USE mydatabase;

This query sets the context to the database named mydatabase.

MySQL USE DATABASE

Step 2: Creating a Table

Create a table to work with:

CREATE TABLE sample_strings (
    id INT AUTO_INCREMENT PRIMARY KEY,
    value VARCHAR(255) NOT NULL
);

This query creates a table named sample_strings with columns for id and value.

MySQL CREATE TABLE

Step 3: Inserting Initial Rows

Insert some initial rows into the table:

INSERT INTO sample_strings (value)
VALUES ('HELLO WORLD'),
       ('MySQL DATABASE'),
       ('STRING FUNCTION'),
       ('Lcase EXAMPLE'),
       ('TEST CASE');

This query inserts five rows into the sample_strings table.

MySQL INSERT INTO TABLE

Step 4: Using LCASE() with WHERE Clause

Use the LCASE() function to convert a string to lowercase:

SELECT value, LCASE(value) AS lowercase_value
FROM sample_strings;

This query retrieves the value column from the sample_strings table and returns the lowercase version of the string.

MySQL LCASE() WITH WHERE CLAUSE

Step 5: Using LCASE() with Multiple Columns

Use the LCASE() function with multiple columns:

SELECT id, value, LCASE(value) AS lowercase_value
FROM sample_strings;

This query retrieves the id and value columns from the sample_strings table and returns the lowercase version of the string.

MySQL LCASE() WITH MULTIPLE COLUMNS

Step 6: Using LCASE() with Constants

Use the LCASE() function with constants:

SELECT LCASE('SAMPLE TEXT') AS lowercase_constant;

This query converts the constant string 'SAMPLE TEXT' to lowercase.

MySQL LCASE() WITH CONSTANTS

Conclusion

The MySQL LCASE() function is a powerful tool for standardizing the case of strings in SQL queries. Understanding how to use the LCASE() function is essential for effective data querying and manipulation in MySQL.