MySQL is a commonly used relational database management system, and open source and free by everyone's favorite. Both large and small projects/programs can use the MySQL database.

First learn about MySQL columns, whose column data types define what data can be stored in this column, such as specifying types as integer, character, currency, date, time, binary, and so on. Each column in a database table has a name and data type, and the type of data stored in each column must be determined at the time of creation. The data type is an indication that SQL knows the type of data stored in each column and determines how SQL interacts with the stored data. The main data types of MySQL are strings, numbers, and date and time.

MySQL also has many built-in functions, such as MySQL strings, numbers, dates and advanced functions are:

ASCII

The above functions can return ASCII values for specific characters.

If you need to calculate the length of a string (in characters)

CHAR_LENGTH

perhaps

CHARACTER_LENGTH

Add two or more expressions together:

CONCAT

To add two or more expressions together:

FIELD

Numbers are formatted in a format like "#,###,###". ## ", rounded to the specified number of decimal places:

FORMAT

To convert a string to lowercase:

LCASE

Returns the location of the first occurrence of the substring in the string:

LOCATE

Extract substrings from a string anywhere:

MID

Returns the location of the first occurrence of the substring in the string:

POSITION

Right-fill one string with another to a certain length:

RPAD

In addition to the above basic command line, MySQL has many more functional applications. MySQL also supports anti-lock braking systems, and the ABS () function returns the absolute value (positive value) of a number:

ABS(number)

Note that this usage needs to be implemented from MySQL 4.0 onwards.