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How do I remove a MySQL database?
...from my last question that a problem caused some more problems, Reading MySQL manuals in MySQL monitor?
6 Answers
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How big can a MySQL database get before performance starts to degrade
At what point does a MySQL database start to lose performance?
15 Answers
15
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What's the difference between RANK() and DENSE_RANK() functions in oracle?
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Error :SQL Error: ORA-00923: FROM keyword not found where expected
– zloctb
Aug 18 '15 at 8:07
add a commen...
django test app error - Got an error creating the test database: permission denied to create databas
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Though the OP used postgresql, if you are using mysql you will have the same error. You can fix it for mysql with: => GRANT ALL ON *.* TO django@localhost; I originally tried to only GRANT CREATE... but then could not SELECT or DROP the created d...
Add unique constraint to combination of two columns
...can often be better to check for this violation first, before just letting SQL Server try to insert the row and returning an exception (exceptions are expensive).
http://www.sqlperformance.com/2012/08/t-sql-queries/error-handling
http://www.mssqltips.com/sqlservertip/2632/checking-for-potential-co...
How to list active / open connections in Oracle?
...lect * from FROM v$session Error at Command Line:1 Column:14 Error report: SQL Error: ORA-00903: invalid table name 00903. 00000 - "invalid table name" *Cause: *Action:
– pistacchio
Jun 25 '09 at 10:22
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MySQL: How to copy rows, but change a few fields?
...s or something and you don't want to type them all, then you could write a SQL statement to build your SQL statement :). The way you would do it would be to use the information_schema to get the column names for the table. But that's really overkill, I'd just type out the column names.
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Is there a way to loop through a table variable in TSQL without using a cursor?
... depends on the structure and volume of your data.
Note: If you are using SQL Server you would be better served using:
WHILE EXISTS(SELECT * FROM #Temp)
Using COUNT will have to touch every single row in the table, the EXISTS only needs to touch the first one (see Josef's answer below).
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Proper Linq where clauses
...ually makes depends on the implementation of Where being called. If it's a SQL-based provider, I'd expect the two to end up creating the same SQL. If it's in LINQ to Objects, the second will have fewer levels of indirection (there'll be just two iterators involved instead of four). Whether those lev...
MySQL order by before group by
... table, on both values you will return the full details of that post.
See SQL Fiddle with Demo.
To expand on my comments about using a subquery to accurate return this data.
MySQL does not force you to GROUP BY every column that you include in the SELECT list. As a result, if you only GROUP BY ...