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MySQL Error 1093 - Can't specify target table for update in FROM clause
...s question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple enough to re-shape the query, lose the subquery and join th...
Delete duplicate rows from small table
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DELETE FROM dupes a
WHERE a.ctid <> (SELECT min(b.ctid)
FROM dupes b
WHERE a.key = b.key);
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Generate GUID in MySQL for existing Data?
...e BEFORE UPDATE on YourTable
FOR EACH ROW
BEGIN
SET new.guid_column := (SELECT UUID());
END
//
Then execute
UPDATE YourTable set guid_column = (SELECT UUID());
And DROP TRIGGER beforeYourTableUpdate;
UPDATE
Another solution that doesn't use triggers, but requires primary key or unique inde...
C# using streams
...itionally, StreamReader and StreamWriter are for reading and writing TEXT (character) streams.
– 1c1cle
Feb 25 '15 at 1:44
1
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Add centered text to the middle of a -like line
... be specified in em units. To get hr width, use (.divider width minus # of chars) / 2 .
– Kelvin
Jan 31 '13 at 22:38
13
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IIS7 Permissions Overview - ApplicationPoolIdentity
...eplace this text below if it is named differently)
Open Windows Explorer
Select a file or directory.
Right click the file and select "Properties"
Select the "Security" tab
Click the "Edit" and then "Add" button
Click the "Locations" button and make sure you select the local machine. (Not the Windo...
How to “git show” a merge commit with combined diff output even when every changed file agrees with
...ng this on the git repository on a8e4a59 shows a combined diff (plus/minus chars in one of 2 columns). As the git-show manual mentions, it pretty much delegates to 'git diff-tree' so those options look useful.
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
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Try the Database Object Size Functions. An example:
SELECT pg_size_pretty(pg_total_relation_size('"<schema>"."<table>"'));
For all tables, something along the lines of:
SELECT
table_schema || '.' || table_name AS table_full_name,
pg_size_pretty(pg_total_...
Distinct in Linq based on only one field of the table
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Try this:
table1.GroupBy(x => x.Text).Select(x => x.FirstOrDefault());
This will group the table by Text and use the first row from each groups resulting in rows where Text is distinct.
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Reading CSV files using C#
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Surely a char-based approach is more natural for this sort of problem than a regex. Depending on the presence of quotation marks the behavior is supposed to be different.
– Casey
May 9 '16 at 1:...