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What is declarative programming? [closed]
... figure out the how.
Examples of declarative programming languages are SQL and Prolog.
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edited Aug 28 '16 at 9:19
Aquarius_...
SQL query return data from multiple tables
...roduce them if your database doesn't support them) - this is a function of SQL-Server (see info) and part of the reason I wrote this whole thing in the first place.
Part 2
Subqueries - what they are, where they can be used and what to watch out for
Cartesian joins AKA - Oh, the misery!
There a...
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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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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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...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
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To answer your concerns:
MySQL >= 5.1.17 (or >= 5.1.21 for the PREPARE and EXECUTE statements) can use prepared statements in the query cache. So your version of MySQL+PHP can use prepared statements with the query cache. However, make careful no...
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...
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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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...