mysql string to decimal

There are non-standard data types such as float,double in MySQL, as well as standard data types such as decimal. The difference is that non-standard types, such as float,double, hold approximate values in db, while decimal saves values as strings.

String functionsstring comparison functionsIf the length of the result is greater than the maximum value of the Max_allowed_packet system variable, the return value of the string value function is null. See section 7.5.2, "Tuning server parameters."

A string or string (string) is a finite sequence consisting of 0 or more characters. Generally recorded as s= ' a1a2 an ' (n>=0). It is the data type that represents text in the programming language. A string is usually used as an action object,

Generally, the entire string is used as the operation object, for example: search for a substring in a substring, obtain a substring, insert a substring at a certain position in the substring, and delete a substring. Generally, the entire string is

String function string comparison function if the result length is greater than the maximum value of the max_allowed_packet system variable, the return value of the string value function is NULL. See section 7.5.2 "Adjust server Parameters ". String

Generally, the entire string is used as the operation object, for example: search for a substring in a substring, obtain a substring, insert a substring at a certain position in the substring, and delete a substring. The required and sufficient

In MySQL data types, such as Int,float,double,char,decimal, and so on, they all have their own role, below we will mainly introduce the MySQL data type of the role and use of the decimal type.The value that is normally given to a floating-point

Float and decimal type bitsCN.com in MySQL Float and decimal types in MySQL Float and double are prone to errors. when the precision requirements are relatively high, decimal is recommended for storage. decimal is stored in mysql memory as a

It is possible for a program to know that the float type is a floating point number (that is, a decimal type), but there is a downside to float, and when the data you give is an integer, it is treated as an integer. So we have a natural problem

The problem of formatting the floating-point number, using Format (col,2) to retain the two-bit decimal point, there is a problem, such as the following statement, after we give a workaroundSELECT FORMAT (12562.6655,2);Results: 12,562.67View