REGEXP_SUBSTR()
Description
REGEXP_SUBSTR()
is used to return the substring of the string expr
that matches the regular expression pattern pat
.
Syntax
> REGEXP_SUBSTR(expr, pat[, pos[, occurrence[, match_type]]])
Explanations
-
expr
: This is the original string in which to look for matches. -
pat
: This is a regular expression pattern, the function will look for strings that match this pattern. -
pos
: The position in expr at which to start the search. If omitted, the default is 1. -
occurrence
: Which occurrence of a match to replace. If omitted, the default is 0 (which means replace all occurrences). -
match_type
: The optionalmatch_type
argument is a string that may contain any or all the following characters specifying how to perform matching:'c'
: Case-sensitive matching by default.'i'
: Case-insensitive matching.'n'
: The.
character matches line terminators. The default is for.
matching to stop at the end of a line.'m'
: Multiple-line mode. Recognize line terminators within the string. The default behavior is to match line terminators only at the start and end of the string expression.'u'
: Unix-only line endings. Only the newline character is recognized as a line ending by the ., ^, and $ match operators.
Examples
mysql> SELECT REGEXP_SUBSTR('1a 2b 3c', '[0-9]a');
+---------------------------------+
| regexp_substr(1a 2b 3c, [0-9]a) |
+---------------------------------+
| 1a |
+---------------------------------+
1 row in set (0.00 sec)
mysql> SELECT REGEXP_SUBSTR('Lend for land', '^C') Result;
+--------+
| Result |
+--------+
| NULL |
+--------+
1 row in set (0.00 sec)