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MySQL Error 1093 - Can't specify target table for update in FROM clause
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Update: This answer covers the general error classification. For a more specific answer about how to best handle the OP's exact query, please see other answers to this question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:...
How to reset sequence in postgres and fill id column with new data?
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Best answer for my case too. I combine this answer with this one, which explains the ALTER SEQUENCE command ... so I changed 'seq' by mytable_id_seq where 'mytable' is my table name and 'id' is the name of my serial column
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Best practice for nested fragments in Android 4.0, 4.1 (
I'm writing an app for 4.0 and 4.1 tablets, for which I do not want to use the support libraries (if not needed) but the 4.x api only therefore.
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How to adjust layout when soft keyboard appears
...y and this will adjust the layout resize option.
some source code below for layout design
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
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What does “for” attribute do in HTML tag?
...='theinput' id='theinput'>
</label>
The other way is to use the for attribute, giving it the ID of the associated input:
<label for="theinput">Input here:</label>
<input type='text' name='whatever' id='theinput'>
This is especially useful for use with checkboxes and b...
SQL variable to hold list of integers
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Thanks for that but again it requires me to rewrite the way the variable is read in the query. I have to keep it the same.
– ErickTreetops
Aug 27 '13 at 1:20
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SQL JOIN - WHERE clause vs. ON clause
... Orders.ID = 12345
The first will return an order and its lines, if any, for order number 12345. The second will return all orders, but only order 12345 will have any lines associated with it.
With an INNER JOIN, the clauses are effectively equivalent. However, just because they are functionally...
What is the purpose of Android's tag in XML layouts?
...that are simply used to wrap other views and serve no purpose themselves.
For example, if you were to <include/> a layout from another file without using merge, the two files might look something like this:
layout1.xml:
<FrameLayout>
<include layout="@layout/layout2"/>
</F...
DISTINCT for only one column
... I must investigate this PARTITION clause, never seen it in action before. Thanks for the example
– LorenVS
Feb 16 '11 at 20:41
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Add new column with foreign key constraint in one command
I am trying to add a new column that will be a foreign key. I have been able to add the column and the foreign key constraint using two separate ALTER TABLE commands:
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