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Count(*) vs Count(1) - SQL Server
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The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
get list of pandas dataframe columns based on data type
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If you are just selecting columns by data type, then this answer is obsolete. Use select_dtypes instead
– Ted Petrou
Nov 3 '17 at 16:58
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Professional jQuery based Combobox control? [closed]
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If I already select one value, then click arrow it only show the selected value, not all value.
– linbo
Oct 10 '12 at 11:55
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How can I get the list of a columns in a table for a SQLite database?
...(first_name varchar, last_name varchar, email_address varchar);
sqlite> select * from sqlite_master;
table|people|people|2|CREATE TABLE people (first_name varchar, last_name varchar, email_address varchar)
To get column information you can use the pragma table_info(table_name) statement:
sqlit...
How to copy a selection to the OS X clipboard
I have an area selected in Vim. How can I copy it into the OS X clipboard?
27 Answers
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Get current AUTO_INCREMENT value for any table
...'TableName' ;
You can get exactly this information by using this query:
SELECT `AUTO_INCREMENT`
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'DatabaseName'
AND TABLE_NAME = 'TableName';
share
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How to get the number of days of difference between two dates on mysql?
...lues are
used in the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------...
Any gotchas using unicode_literals in Python 2.6?
..., the clearer the code is, since what you want is to manipulate strings of characters, not arrays of bytes with an externally implied encoding.
– Eric O Lebigot
Sep 3 '10 at 12:35
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Where can I get Google developer key
...velopers Console interface was overhauled again. For the new interface:
Select your project from the toolbar.
Open the "Gallery" using hamburger menu icon on the left side of the toolbar and select 'API Manager'.
Click 'Credentials' in the left-hand navigation.
Alternatively, you can click 'Sw...
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...