mysql convert characters

In MySQL database, we usually need to convert numbers to string type when converting them to characters. In this article, we will explain how to convert numbers to characters using different methods in MySQL.

Method 1: Use the CAST function

Use MySQL's CAST function to convert numbers into strings. The following is the basic syntax for using CAST to convert numbers into characters:

CAST(expression AS type)

Here, expression represents the number that needs to be converted, and type represents the character type that needs to be converted. For example, the following is an example of converting a number to the CHAR type:

SELECT CAST(123 AS CHAR);

The result will be returned as the "123" string.

Method 2: Use the CONVERT function

There is another way to convert numbers into strings, which is to use the CONVERT function of MySQL. The following is the basic syntax for using CONVERT to convert numbers to characters:

CONVERT(expression,type)

Here, expression represents the number that needs to be converted, and type represents the character type that needs to be converted. For example, the following is an example of converting a number to the CHAR type:

SELECT CONVERT(123,CHAR);

The result will be returned as the "123" string.

Method 3: Use the FORMAT function

If you need to display numbers in a specific format, you can use MySQL's FORMAT function. For example, if you want to display numbers separated by commas per thousand, you can use the following syntax:

FORMAT(expression, decimals)

Here, expression represents the number that needs to be converted, and decimals represents the number of digits to retain after the decimal point. For example, the following is an example of using the FORMAT function to convert a number to a character:

SELECT FORMAT(12345.67, 2);

The result will be returned as the string "12,345.67".

Method 4: Use the CONCAT function

If you need to connect numbers and other characters, you can use MySQL's CONCAT function. The following is the basic syntax for converting numbers to characters using the CONCAT function:

CONCAT(expr1, expr2,...)

Here, expr1, expr2 represent the values you need to concatenate. For example, here is an example of using the CONCAT function to concatenate numbers and characters:

SELECT CONCAT(123, ' years old');

The result will be the "123 years old" string returned.

Summary:

In MySQL, numbers can be converted into characters and strings using the CAST, CONVERT, FORMAT, and CONCAT functions. You can choose the appropriate function to complete your conversion operation according to different requirements.

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