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SQL Server String or binary data would be truncated
...oject. I am getting the following error when I try to insert data from one table into another table (SQL Server 2005):
20 A...
What is the difference between Views and Materialized Views in Oracle?
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What is the meaning of DISK based? Is it mean table is not part of DISK? Is it stored in a file and DISK access is faster that File access ....?
– Kanagavelu Sugumar
Sep 16 '14 at 3:55
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Get local IP address
...xistence of the route to the destination according to the system's routing table and setting the local endpoint accordingly. The last part seems to be undocumented officially but it looks like an integral trait of Berkeley sockets API (a side effect of UDP "connected" state) that works reliably in b...
How to create a unique index on a NULL column?
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create unique index UIX on MyTable (Column1) where Column1 is not null
– Jørn Schou-Rode
Dec 2 '10 at 14:54
1
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How to get ID of the last updated row in MySQL?
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I've found an answer to this problem :)
SET @update_id := 0;
UPDATE some_table SET column_name = 'value', id = (SELECT @update_id := id)
WHERE some_other_column = 'blah' LIMIT 1;
SELECT @update_id;
EDIT by aefxx
This technique can be further expanded to retrieve the ID of every row affected by...
When should I use a composite index?
For example, I have a homes table:
9 Answers
9
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How to prevent gcc optimizing some statements in C?
In order to make a page dirty (switching on the dirty bit in the page table entry), I touch the first bytes of the page like this:
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Multiple select statements in Single query
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SELECT (
SELECT COUNT(*)
FROM user_table
) AS tot_user,
(
SELECT COUNT(*)
FROM cat_table
) AS tot_cat,
(
SELECT COUNT(*)
FROM course_table
) AS tot_course
share
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How to limit the maximum value of a numeric field in a Django model?
...t the validation in a form. The question of which range of numbers is acceptable is as much a part of the model as is the question of which kind of number is acceptable. I don't want to have to tell every form through which the model is editable, just which range of numbers to accept. This would vi...
How to select from subquery using Laravel Query Builder?
...Abc::where(..)->groupBy(..); // Eloquent Builder instance
$count = DB::table( DB::raw("({$sub->toSql()}) as sub") )
->mergeBindings($sub->getQuery()) // you need to get underlying Query Builder
->count();
Mind that you need to merge bindings in correct order. If you have ot...