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Dolphin DB : : :在由扼杀物组成的病媒中,如何在奇-宽度扼杀之前添加“0” ?
原标题:DolphinDB: in a vector consisting of strings, how to add a “0“ before odd-length strings?

支撑一栏包含有奇数或偶数特性的插图。 我愿在奇伦格字节之前加上“0”的特性,使用奇伦格言。

select Code, iif(Code.strlen() % 2 = 0, Code, `0 + Code) from tmpCode

然而,需要5GB的记忆,需要很长的时间才能在30MB表上执行上述声明。 是否有更有效的办法实现这一目标?

问题回答

您可使用<代码>lpad功能界定如下的功能:

def evenLPad(str, pad): lpad{,,pad}:E(str, 2*ceil strlen(str)2)

如果体力太大,你还可以提到以下文字,其速度为20%:

def evenLPad(str, pad): lpad{,,pad}:E(str, 254&strlen(str)+1)




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