elt

elt

description

Syntax

VARCHAR elt(INT, VARCHAR,...)

在指定的索引处返回一个字符串。如果指定的索引处没有字符串，则返回NULL。

example

mysql> select elt(1, 'aaa', 'bbb');
+----------------------+
| elt(1, 'aaa', 'bbb') |
+----------------------+
| aaa                  |
+----------------------+
mysql> select elt(2, 'aaa', 'bbb');
+-----------------------+
| elt(2, 'aaa', 'bbb')  |
+-----------------------+
| bbb                   |
+-----------------------+
mysql> select elt(0, 'aaa', 'bbb');
+----------------------+
| elt(0, 'aaa', 'bbb') |
+----------------------+
| NULL                 |
+----------------------+
mysql> select elt(2, 'aaa', 'bbb');
+-----------------------+
| elt(3, 'aaa', 'bbb')  |
+-----------------------+
| NULL                  |
+-----------------------+