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MySQL - UPDATE query based on SELECT Query
...can go here
ANSI SQL syntax:
UPDATE tableA SET validation_check =
(SELECT if(start_DTS > end_DTS, 'VALID', '') AS validation_check
FROM tableA
INNER JOIN tableB ON name_A = name_B
WHERE id_A = tableA.id_A)
Pick whichever one seems most natural to you.
...
CASCADE DELETE just once
...you want to cascade.
DELETE FROM some_child_table WHERE some_fk_field IN (SELECT some_id FROM some_Table);
DELETE FROM some_table;
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Is there a MySQL command to convert a string to lowercase?
...nction is LOWER() or LCASE() (they both do the same thing).
For example:
select LOWER(keyword) from my_table
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How to combine date from one field with time from another field - MS SQL Server
...ro (base date: January 1, 1900)
Adding them returns the correct result.
SELECT Combined = MyDate + MyTime FROM MyTable
Rationale (kudos to ErikE/dnolan)
It works like this due to the way the date is stored as two 4-byte
Integers with the left 4-bytes being the date and the right
4-bytes...
How do I view the full content of a text or varchar(MAX) column in SQL Server 2008 Management Studio
...ta.
DECLARE @S varchar(max) = 'A'
SET @S = REPLICATE(@S,100000) + 'B'
SELECT @S as [XML_F52E2B61-18A1-11d1-B105-00805F49916B]
In SSMS (at least versions 2012 to current of 18.3) this displays the results as below
Clicking on it opens the full results in the XML viewer. Scrolling to the rig...
Xcode 4 - “Archive” is greyed out?
...
You have to select the device in the schemes menu in the top left where you used to select between simulator/device. It won’t let you archive a build for the simulator.
Or you may find that if the iOS device is already selected the ar...
How to achieve code folding effects in Emacs?
...on: C-h k C-x $
tells us that the above key combination is calling
set-selective-display, a function that takes one numerical argument
(the M-1 prefix passes 1 as the value of that argument) and,
unsurprisingly, sets the variable selective-display to the value of
that argument.
from mino...
MySQL Data - Best way to implement paging?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ro...
What is the dual table in Oracle?
...
It's a sort of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
...
Color different parts of a RichTextBox string
...pendText(this RichTextBox box, string text, Color color)
{
box.SelectionStart = box.TextLength;
box.SelectionLength = 0;
box.SelectionColor = color;
box.AppendText(text);
box.SelectionColor = box.ForeColor;
}
}
And this is how you would use it:
var...