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Dropping Unique constraint from MySQL table
...AINT unq_tab_id UNIQUE(id));
-- checking constraint name if autogenerated
SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE TABLE_NAME = 'tab';
-- dropping constraint
ALTER TABLE tab DROP CONSTRAINT unq_tab_id;
db<>fiddle demo
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Programmatically creating Markdown tables in R with KnitR
...:) Please note that you might also use the generic S3 method to save a few chars to type, like: pander(head(iris)[, 1:3])
– daroczig
Mar 19 '13 at 9:23
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Add a properties file to IntelliJ's classpath
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Try this:
Go to Project Structure.
Select your module.
Find the folder in the tree on the right and select it.
Click the Sources button above that tree (with the blue folder) to make that folder a sources folder.
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SVN (Subversion) Problem “File is scheduled for addition, but is missing” - Using Versions
...isplaying the same message. I simply right clicked the offending files and selected 'Revert...' from the right-click menu and all was good.
Basically Versions (actually Subversion) thinks you still want to add the file, but it cannot find it because you deleted it in the file system. The Revert opt...
SQLite: How do I save the result of a query as a CSV file?
... file output.
sqlite> .mode csv
sqlite> .output test.csv
sqlite> select * from tbl1;
sqlite> .output stdout
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How to select the nth row in a SQL database table?
I'm interested in learning some (ideally) database agnostic ways of selecting the n th row from a database table. It would also be interesting to see how this can be achieved using the native functionality of the following databases:
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MySQL how to join tables on two fields
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SELECT *
FROM t1
JOIN t2 USING (id, date)
perhaps you'll need to use INNEER JOIN or
where t2.id is not null
if you want results only matching both conditions
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How to do what head, tail, more, less, sed do in Powershell? [closed]
...option for reading a text file. You can then filter further:
gc log.txt | select -first 10 # head
gc -TotalCount 10 log.txt # also head
gc log.txt | select -last 10 # tail
gc -Tail 10 log.txt # also tail (since PSv3), also much faster than above option
gc log.txt | more #...
Open two instances of a file in a single Visual Studio session
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Here's how to do it...
Select the tab you want two copies of
Select menu Window → New Window from the menu.
Right click the new tab and select New Vertical Tab Group
If New Window is not listed in the *Window menu note that the command does exi...
How to get city name from latitude and longitude coordinates in Google Maps?
... while ((b = stream.read()) != -1) {
stringBuilder.append((char) b);
}
} catch (ClientProtocolException e) {
} catch (IOException e) {
}
JSONObject jsonObject = new JSONObject();
try {
jsonObject = new JSONObject(stringBuilder.toString());
} c...