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MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
What is main difference between INSERT INTO table VALUES .. and INSERT INTO table SET ?
3 Answers
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SQL Call Stored Procedure for each Row without using a cursor
How can one call a stored procedure for each row in a table, where the columns of a row are input parameters to the sp without using a Cursor?
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How to delete duplicate rows in SQL Server?
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RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (result is different; I assume that it's due to a typo on your part)
COL1 COL2 COL3 COL4 COL5 COL6 COL7
john 1 1 1 1 1 1
sa...
How to combine two or more querysets in a Django view?
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If merging querysets from the same table to perform an OR query, and have duplicated rows you can eliminate them with the groupby function: from itertools import groupby unique_results = [rows.next() for (key, rows) in groupby(result_list, key=lambda obj: obj...
Get top 1 row of each group
I have a table which I want to get the latest entry for each group. Here's the table:
20 Answers
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How to play audio?
...ats as HTML5’s <audio>. Wikipedia has a audio format compatibility table. new Audio() can play WAV files in all browsers except Internet Explorer.
– Rory O'Kane
Mar 15 '15 at 14:18
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When and why are database joins expensive?
...nality when (if) they set up indexes.
It is important to understand that table scans (examination of every row in a table in the course of producing a join) are rare in practice. A query optimiser will choose a table scan only when one or more of the following holds.
There are fewer than 200 row...
SQLAlchemy ORDER BY DESCENDING?
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from sqlalchemy import desc
someselect.order_by(desc(table1.mycol))
Usage from @jpmc26
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How to do INSERT into a table records extracted from another table
I'm trying to write a query that extracts and transforms data from a table and then insert those data into another table. Yes, this is a data warehousing query and I'm doing it in MS Access. So basically I want some query like this:
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SQL Server Output Clause into a scalar variable
Is there any "simple" way to do this or I need to pass by a table variable with the "OUTPUT ... INTO" syntax?
3 Answers
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