Shulou(Shulou.com)05/31 Report--

This article mainly shows you the "MySQL database CAST and CONVERT functions to achieve type conversion example analysis", the content is easy to understand, well-organized, hope to help you solve your doubts, the following let Xiaobian lead you to study and study the "MySQL database CAST and CONVERT functions to achieve type conversion example analysis" this article.

The CAST () and CONVERT () functions of MySQL can be used to get a value of one type and produce a value of another type.

The specific syntax of the two is as follows:

CAST (value as type); CONVERT (value, type)

It is CAST (xxx AS type), CONVERT (xxx, type).

There are limits to the types that can be converted. This type can be one of the following values:

Binary, same effect with binary prefix: BINARY

For example, the statement should be Create_Time like binary CONCAT ('%', # {createTime},'%') when using like fuzzy search for fields of date type

Character type, with parameter: CHAR ()

Date: DATE

Time: TIME

Date and time type: DATETIME

Floating point numbers: DECIMAL

Integer: SIGNED

Unsigned integers: UNSIGNED

Here are a few examples:

Example one

Mysql > SELECT CONVERT; +-+ | CONVERT ('23rd Magazine signed) | +-+ | 23 | +-+ 1 row in set

This example is to convert varchar types to int types.

Example two

Mysql > SELECT CAST ('125e342.83' AS signed); +-+ | CAST (' 125e342.83' AS signed) | +-+ | 125 | +-+ 1 row in set

Example 3

Mysql > SELECT CAST ('3.35' AS signed); +-+ | CAST (' 3.35' AS signed) | +-+ | 3 | +-+ 1 row in set

As in the example above, convert varchar to int with cast (an as signed), where an is a string of type varchar.

Example 4

In SQL Server, the following code demonstrates that the hexadecimal storage of the date store represents the result when the datetime variable contains only a simple date and a simple time.

DECLARE @ dt datetime-- simple date SET @ dt='1900-1-2'SELECT CAST (@ dt as binary (8))-result: 0x0000000100000000Lue simple time SET @ dt='00:00:01'SELECT CAST (@ dt as binary (8))-result: 0x000000000000012C

The type conversion of MySQL is the same as SQL Server, except that the type parameters are slightly different: CAST (xxx AS type), CONVERT (xxx, type).

The above is all the contents of the article "sample Analysis of Type conversion between CAST and CONVERT functions in MySQL Database". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.