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How can I select multiple columns from a subquery (in SQL Server) that should have one record (selec
I Know I can select a column from a subquery using this syntax:
5 Answers
5
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How to select rows from a DataFrame based on column values?
How to select rows from a DataFrame based on values in some column in Pandas?
10 Answers
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Pycharm: run only part of my Python file
... easier way.
go to File -> Settings -> Keymap
Search for Execute Selection in Console and reassign it to a new shortcut, like Crl + Enter.
This is the same shortcut to the same action in Spyder and R-Studio.
sha...
Naming convention for unique constraint
...imary key doesn't get a sequence number since there can be only one. The 2-char alpha suffix meanings are:
PK: Primary Key
AK: Alternate Key
FK: Foreign Key
IX: IndeX
CK: ChecK
DF: DeFault
I generally want to group metadata/system catalog data by the controlling object rather than by object type...
What's the difference between MyISAM and InnoDB? [duplicate]
... on the table, and while that lock is held, no other session can perform a SELECT or a DML operation on the table.
Those two specific engines you asked about (InnoDB and MyISAM) have different design goals. MySQL also has other storage engines, with their own design goals.
So, in choosing between In...
How do I set the time zone of MySQL?
...+00:00'
@@global.time_zone variable
To see what value they are set to:
SELECT @@global.time_zone;
To set a value for it use either one:
SET GLOBAL time_zone = '+8:00';
SET GLOBAL time_zone = 'Europe/Helsinki';
SET @@global.time_zone = '+00:00';
(Using named timezones like 'Europe/Helsinki' ...
What does apply_filters(…) actually do in WordPress?
...the following sequence of functions:
wptexturize
convert_smilies
convert_chars
wpautop
shortcode_unautop
prepend_attachment
do_shortcode
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Are static fields inherited?
...{
public:
SomeDerivedClass() {total++;}
};
int main(int argc, char ** argv)
{
SomeClass A;
SomeClass B;
SomeDerivedClass C;
A.Print("A");
B.Print("B");
C.Print("C");
return 0;
}
And the results:
A.total = 4
B.total = 4
C.total = 4
...
How does the SQL injection from the “Bobby Tables” XKCD comic work?
..., the parenthesis makes more sense with an INSERT. Thinking backwards, the SELECT would not run anyway as the Insert of the Little Bobby Tables in the table would have already dropped the table.
– ypercubeᵀᴹ
Jan 21 '13 at 21:41
...
Copy a table from one database to another in Postgres
... follow these steps:
In pgAdmin, right click the table you want to move, select "Backup"
Pick the directory for the output file and set Format to "plain"
Click the "Dump Options #1" tab, check "Only data" or "only Schema" (depending on what you are doing)
Under the Queries section, click "Use Colu...