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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...
Initialize a byte array to a certain value, other than the default null? [duplicate]
...rrectly, even to fill with 0x00 bytes: Encoding.ASCII.GetBytes(new string((char)0, 100));
– Ben
Aug 3 '16 at 19:44
Fun...
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...
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 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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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 |
+--------------...
Error 1046 No database Selected, how to resolve?
...ation.
If you're trying to do this via MySQL Workbench...
...you need to select the appropriate database/catalog in the drop down menu found above the :Object Browser: tab. You can specify the default schema/database/catalog for the connection - click the "Manage Connections" options under the SQL...
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...
How to list active / open connections in Oracle?
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Error starting at line 1 in command: select * from FROM v$session Error at Command Line:1 Column:14 Error report: SQL Error: ORA-00903: invalid table name 00903. 00000 - "invalid table name" *Cause: *Action:
– pistacchio
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