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What CSS selector can be used to select the first div within another div
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Can you tell me how to select all div except first/last div?
– Tân
Jul 5 '16 at 9:17
5
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MySQL and GROUP_CONCAT() maximum length
...You should use it like this.
SET SESSION group_concat_max_len = 1000000;
select group_concat(column) from table group by column
You can do this even in sharing hosting, but when you use an other session, you need to repeat the SET SESSION command.
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Frequency table for a single variable
... the columns as such
[my_series[c].value_counts() for c in list(my_series.select_dtypes(include=['O']).columns)]
Breakdown:
my_series.select_dtypes(include=['O'])
Selects just the categorical data
list(my_series.select_dtypes(include=['O']).columns)
Turns the columns f...
关于php的socket初探 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...连接的模型都应该被称为多路复用，目前比较常用的有 select/poll/epoll/kqueue 这些 IO 模型（目前也有像 Apache 这种每个连接用单独的进程/线程来处理的 IO 模型，但是效率相对比较差，也很容易出问题，所以暂时不做介绍了）。在...
PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
How to add external library in IntelliJ IDEA?
...ect top level, refresh/synchronize)
Expand libs and right click on the jar
Select "Add as Library"
Done
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Keyboard shortcut to paste clipboard content into command prompt window (Win XP) [closed]
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Just to explain selecting also: ALT+SPACE+E+K <-- for copy . and navigate up , down , left , right with arrows Shift + right arrow <-- for selecting the text ALT+SPACE+E+P <-- for paste.
– Yordan Georgiev
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Give all the permissions to a user on a DB
...%', ( -- use instead of EXECUTE to see generated commands
EXECUTE (
SELECT string_agg(format('GRANT USAGE ON SCHEMA %I TO my_user', nspname), '; ')
FROM pg_namespace
WHERE nspname <> 'information_schema' -- exclude information schema and ...
AND nspname NOT LIKE 'pg\_%' ...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...
How can I convert a string to upper- or lower-case with XSLT?
...hod of case conversion is translate():
<xsl:variable name="lowercase" select="'abcdefghijklmnopqrstuvwxyz'" />
<xsl:variable name="uppercase" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'" />
<xsl:template match="/">
<xsl:value-of select="translate(doc, $lowercase, $uppercase)" /&g...