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Insert a line at specific line number with sed or awk
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243
sed -i '8i8 This is Line 8' FILE
inserts at line 8
8 This is Line 8
into file FILE
-i doe...
How can I select multiple columns from a subquery (in SQL Server) that should have one record (selec
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130
Here's generally how to select multiple columns from a subquery:
SELECT
A.SalesOrderID,
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Dropping Unique constraint from MySQL table
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A unique constraint is also an index.
First use SHOW INDEX FROM tbl_name to find out the nam...
How to ignore deprecation warnings in Python
...tter though to resolve the issue, by casting to int.
(Note that in Python 3.2, deprecation warnings are ignored by default.)
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How to enable mod_rewrite for Apache 2.2
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edited Apr 13 '18 at 7:49
Elangovan
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Node.js: printing to console without a trailing newline?
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edited Aug 30 '13 at 20:15
Akseli Palén
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Relative frequencies / proportions with dplyr
...()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it ea...
MySQL load NULL values from CSV data
I have a file that can contain from 3 to 4 columns of numerical values which are separated by comma. Empty fields are defined with the exception when they are at the end of the row:
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What are good message queue options for nodejs? [closed]
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edited May 23 '17 at 12:10
Community♦
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answered Jan 15 '11 at 20:37
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How to match “any character” in regular expression?
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answered May 26 '10 at 12:31
Delan AzabaniDelan Azabani
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