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Python Pandas: Get index of rows which column matches certain value
... [57]: idx
Out[57]: Int64Index([10, 40, 50], dtype='int64')
then you can select the rows using loc instead of iloc:
In [58]: df.loc[idx]
Out[58]:
BoolCol
10 True
40 True
50 True
[3 rows x 1 columns]
Note that loc can also accept boolean arrays:
In [55]: df.loc[df['BoolCol']]
Ou...
How to check if a database exists in SQL Server?
...script:
DECLARE @dbname nvarchar(128)
SET @dbname = N'Senna'
IF (EXISTS (SELECT name
FROM master.dbo.sysdatabases
WHERE ('[' + name + ']' = @dbname
OR name = @dbname)))
-- code mine :)
PRINT 'db exists'
share
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Selecting the last value of a column
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Another good resource is the selected answer at productforums.google.com/forum/#!topic/docs/p3t3feg7Jic which shows how to get the first, last, or nth row in a FILTER()ed range, similar to @Geta's answer.
– Aaron Blenkush
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What are the uses for Cross Join?
...ly, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might c...
ORACLE 常用日期函数 - ORACLE - 清泛IT论坛，有思想、有深度
...日期。如果给出一负数，返回值日期之前几个月日期。
select add_months(to_date('20150201','yyyymmdd'), -1) from dual
结果：2015/1/1
相应的，加减天数add_days函数是不存在的，直接用+、-即可，例如：
select to_date('20150201','yyyymmdd')+1 from dual
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How can I use swift in Terminal?
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sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
then you can do one of these:
xcrun swift
lldb --repl
As of Xcode 6.1 - typing swift in the terminal launches the REPL as well.
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What is the best collation to use for MySQL with PHP? [closed]
...ng utf8_general_ci.
MySQL will not distinguish between some characters in select statements, if the utf8_general_ci collation is used. This can lead to very nasty bugs - especially for example, where usernames are involved. Depending on the implementation that uses the database tables, this problem...
“Wrap with try…catch” in IntelliJ?
Can I select a block of code and have IntelliJ wrap it with a "try...catch" ?
9 Answers
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How do I programmatically set the value of a select box element using JavaScript?
I have the following HTML <select> element:
17 Answers
17
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How to stop Visual Studio from opening a file on single click?
...anted to add that the button David is referring to has a tooltip: "Preview Selected Items"
– Bruce van der Kooij
Jan 11 '13 at 9:39
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