SQL -> Funkcie -> Funkcie pre prácu s reťazcami -> SQL - substring

Syntax

SUBSTRING(str,pos)
SUBSTRING(str FROM pos)
SUBSTRING(str,pos,len)
SUBSTRING(str FROM pos FOR len)

Popis

Príkaz jazyka SQL
The forms without a len argument return a substring from string str starting at position pos. The forms with a len argument return a substring len characters long from string str, starting at position pos. The forms that use FROM are standard SQL syntax. Beginning with MySQL 4.1.0, it is possible to use a negative value for pos. In this case, the beginning of the substring is pos characters from the end of the string, rather than the beginning. A negative value may be used for pos in any of the forms of this function.

This function is multi-byte safe.

If len is less than 1, the result is the empty string.

SUBSTR is a synonym for SUBSTRING().

Príklad