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lpad( string, padded_length, [ pad_string ] ) string: 准备被填充的字符串 padded_length: 填充之后的字符串长度 pad_string: 填充字符串,是个可选参数 RPAD:从右边开始填充,用法同LPAD。 1、LPAD函数:oracle数据库函数,是从左边起对指定的字符串进

lpad( string, padded_length, [ pad_string ] )

string:
准备被填充的字符串
padded_length:
填充之后的字符串长度
pad_string:
填充字符串,是个可选参数

RPAD:从右边开始填充,用法同LPAD。

1、LPAD函数:oracle数据库函数,是从左边起对指定的字符串进行指定的字符填充。

实例一:SQL> select lpad('xxvvv',4)||'AAA'||'BBB' from dual;

LPAD('XXVVV',4)||'AAA'||'BBB'
-----------------------------
xxvvAAABBB
SQL> select lpad('xxv',4)||'AAA'||'BBB' from dual;

LPAD('XXV',4)||'AAA'||'BBB'
---------------------------
xxvAAABBB
从左边开始对字符串'AAA'||'BBB'进行填充,填充长度为4(‘xxvvv’是填充字符串,4是填充字符串的长度,若填充字符串长度超过4,则截取前4位填充,若不超过4,则全部填充)

实例二:SQL> select lpad('aaabbb',10,'x') from dual;

LPAD('AAABBB',10,'X')
---------------------
xxxxaaabbb
从左边开始对字符串'AAABBB'进行填充(‘aaabbb’:被填充字符串,10:填充后字符串长度,‘x’:填充字符串,填充后的字符串长度为10)

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