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Declaring a default constraint when creating a table
I am creating a new table in Microsoft SQL server 2000 by writing the code instead of using the GUI, I am trying to learn how to do it "the manual way".
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SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
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Since 3.24.0 SQLite also supports upsert, so now you can simply write the following
INSERT INTO visits (ip, hits)
VALUES ('127.0.0.1', 1)
ON CONFLICT(ip) DO UPDATE SET hits = hits + 1;
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Numbering rows within groups in a data frame
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284
Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
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Force Git to always choose the newer version during a merge?
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2 Answers
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What jsf component can render a div tag?
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235
You can create a DIV component using the <h:panelGroup/>.
By default, the <h:panelGro...
How to create a new language for use in Visual Studio
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62
I would take a look at another language that has already done the legwork of integrating with Vi...
Instance variable: self vs @
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264
Writing @age directly accesses the instance variable @age. Writing self.age tells the object t...
GIT repository layout for server with multiple projects
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2 Answers
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python max function using 'key' and lambda expression
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288
lambda is an anonymous function, it is equivalent to:
def func(p):
return p.totalScore ...
How to know the size of the string in bytes?
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132
You can use encoding like ASCII to get a character per byte by using the System.Text.Encoding cl...