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Row Offset in SQL Server
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I would avoid using SELECT *. Specify columns you actually want even though it may be all of them.
SQL Server 2005+
SELECT col1, col2
FROM (
SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable...
Real life example, when to use OUTER / CROSS APPLY in SQL
...1) Top N per group queries (can be more efficient for some cardinalities)
SELECT pr.name,
pa.name
FROM sys.procedures pr
OUTER APPLY (SELECT TOP 2 *
FROM sys.parameters pa
WHERE pa.object_id = pr.object_id
ORDER BY pr.n...
how to check redis instance version?
...uldn't have helped OP. Still, I think most readers will find issuing info from a client more helpful than running redis-server on the host.
– cluesque
Aug 19 at 14:51
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Convert Rows to columns using 'Pivot' in SQL Server
...9, 3, 87);
If your values are known, then you will hard-code the query:
select *
from
(
select store, week, xCount
from yt
) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) piv;
See SQL Demo
Then if you need to generate the week number dynamically, your code will be:
DECLARE @c...
How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
...
LinkedBlockingQueue vs ConcurrentLinkedQueue
...mes in, and inefficiencies when it's empty (due to waking up unnecessarily from sleeps).
From the docs for BlockingQueue:
BlockingQueue implementations are designed to be used primarily for producer-consumer queues
I know it doesn't strictly say that only blocking queues should be used for pr...
quick random row selection in Postgres
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You might want to experiment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hatchkins)
You must use floor he...
SET versus SELECT when assigning variables?
What are the differences between the SET and SELECT statements when assigning variables in T-SQL?
4 Answers
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What does it mean by select 1 from table?
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SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, c...
How to create a table from select query result in SQL Server 2008 [duplicate]
I want to create a table from select query result in SQL Server, I tried
6 Answers
6
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