March 2021
Intermediate to advanced
265 pages
6h 50m
Chinese
Content preview from Presto实战
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高级
SQL
特性
｜
155
函 数 返回类型 描 述 示 例
length(
string
) BIGINT
返回一个字符串的长度
SELECT length(
saippuakivikauppias
)
lower(
string
) VARCHAR
将字符串转换为小写
SELECT lower(
UPPER
);
lpad(
string, size,
padstring
)
VARCHAR
在字符串左边填充
size
个
padstring
。如果
size
小于
字符串的实际长度，则截断
该字符串
SELECT lpad(
A
, 4, ' ')
ltrim(
string
) VARCHAR
去除头部空格
SELECT ltrim( lpad(
A
, 4, ' ') )
replace(
string,
search, replace
)
VARCHAR
将
string
中的
search
字符
串替换为
replace
字符串
SELECT replace(
555.555.5555, ., -
)
reverse(
string
) VARCHAR
反转字符串
SELECT
reverse(
saippuakivikauppias
)
rpad(
string, size,
padstring
)
VARCHAR
在字符串右边填充
size
个
padstring
。如果
size
小于
字符串的实际长度，则截断
该字符串
SELECT rpad(
A
, 4, #)
rtrim(
string
) VARCHAR
去除尾部空格
SELECT rtrim( rpad(
A
, 4, ' ') )
split(
string, ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.