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MySQL “Group By” and “Order By”
I want to be able to select a bunch of rows from a table of e-mails and group them by the from sender. My query looks like this:
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How to select only date from a DATETIME field in MySQL?
...e a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
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Search for selection in vim
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Check this Vim tip: Search for visually selected text
Or you can simply yank the selected text with y and go to search mode /, then you can paste the last yanked text with Ctrl+R 0
share
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How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
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SQL Server loop - how do I loop through a set of records
how do I loop through a set of records from a select?
8 Answers
8
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How to calculate age (in years) based on Date of Birth and getDate()
...low:
try this:
DECLARE @dob datetime
SET @dob='1992-01-09 00:00:00'
SELECT DATEDIFF(hour,@dob,GETDATE())/8766.0 AS AgeYearsDecimal
,CONVERT(int,ROUND(DATEDIFF(hour,@dob,GETDATE())/8766.0,0)) AS AgeYearsIntRound
,DATEDIFF(hour,@dob,GETDATE())/8766 AS AgeYearsIntTrunc
OUTPUT:
Age...
What is the best way to auto-generate INSERT statements for a SQL Server table?
...2008:
Right-click on the database and go to Tasks > Generate Scripts.
Select the tables (or objects) that you want to generate the script against.
Go to Set scripting options tab and click on the Advanced button.
In the General category, go to Type of data to script
There are 3 options: Schema ...
Postgres manually alter sequence
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The parentheses are misplaced:
SELECT setval('payments_id_seq', 21, true); # next value will be 22
Otherwise you're calling setval with a single argument, while it requires two or three.
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Fix code indentation in Xcode
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Before Xcode 9 (for Xcode 9 see default shortcut below)
select text
right-click
there's a "Re-indent selection" item in popup menu
In XCode 4 there is one more step:
select text
right-click
Click on "Structure"
there's a "Re-indent selection" and other options in popup men...
Insert all values of a table into another table in SQL
.... But the insert statement accepts values, but i would like it to accept a select * from the initial_Table. Is this possible?
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