MySQL > select * from ‘MySQL’ where table (s) where table (s) where table (s) where table (s) where table (s) where table (s) where table (s)

MySQL’s CAST() and CONVERT() functions can be used to take a value of one type and produce a value of another. The syntax is as follows:

CAST(value as type);
 
CONVERT(value, type);
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Binary: There is a limit to the types that binary can convert. This type can be one of the following values:

It is a character with parameters: CHAR() DATE: DATETIME: TIME DATETIME type: DATETIME Floating point: DECIMAL Integer: SIGNED UNSIGNED integer: UNSIGNEDCopy the code

Example:

Description: The product_cat_rank table live_id is an int, and the user_Permission table access_key is a char. The two tables are associated by live_id and access_key.

Dlpcrd. live_id is an int. Select dlpcrd.id, vupfrom product_cat_rank dlpcrd 
join user_permission vup on vup.access_key = cast(dlpcrd.live_id as char)
where vup.access_key = '1234'; Dlpcrd. live_id is an int. Select dlpcrd.id, vupfrom product_cat_rank dlpcrd 
join user_permission vup on vup.access_key = convert(dlpcrd.live_id, char)
where vup.access_key = '1234';

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