How is the to_char function used in MySQL?

There is no built-in to_char function in MySQL. The to_char function is a function in the Oracle database used to convert date, number, string, and other data types into a specified format of a string.

In MySQL, you can use other functions to achieve similar functionality. Here are some commonly used functions:

1. The DATE_FORMAT function is used to format a date in a specified string format. In this function, date is the date value, and format is the string used for formatting the date. For example, the date can be formatted as ‘YYYY-MM-DD’ using the ‘%Y-%m-%d’ format.
   Example: SELECT DATE_FORMAT(NOW(), ‘%Y-%m-%d’);
2. The function CAST(expr AS type) is used to convert an expression into a specified data type. In this case, expr is the expression to be converted and type is the data type to convert to. For example, you can convert a string to an integer type.
   Example: SELECT CAST(‘123’ AS SIGNED);
3. The CONCAT function is used to combine multiple expressions into one string. expr1, expr2, … are the expressions to be combined. For example, you can combine multiple strings into one string.
   Example: SELECT CONCAT(‘Hello’, ‘ ‘, ‘World’);

Please note that the above functions are commonly used in MySQL, but they are not a complete substitute for the to_char function. If more precise functionality is needed, you may need to use other functions or create custom functions.