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Unique constraint on multiple columns
How do I add a unique constraint for columns fcode, scode, dcode with t-sql and/or management studio ? fcode, scode, dcode must be unique together.
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Where IN clause in LINQ [duplicate]
How to make a where in clause similar to one in SQL Server?
8 Answers
8
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MySQL show status - active or total connections?
...Connections
The number of connection attempts (successful or not) to the MySQL server.
You can see the number of active connections either through the Threads_connected status variable:
Threads_connected
The number of currently open connections.
mysql> show status where `variable_name` = 'Thre...
What size do you use for varchar(MAX) in your parameter declaration?
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Use nvarchar(max) in sql and define length -1 with SqlDbType.NVarchar in c#
– Romil Kumar Jain
Jun 30 '16 at 9:23
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Get table column names in MySQL?
Is there a way to grab the columns name of a table in mysql?
using php
19 Answers
19
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Quick easy way to migrate SQLite3 to MySQL? [closed]
Anyone know a quick easy way to migrate a SQLite3 database to MySQL?
17 Answers
17
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How to take MySQL database backup using MySQL Workbench?
How to take database backup using MySQL Workbench? Can we take backup in the following ways-
9 Answers
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“Server” vs “Data Source” in connection string
I'm new to SqlServer, right now I have SqlLocalDb installed to work locally. Good, but I can see two connection strings typically and both works:
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Reference alias (calculated in SELECT) in WHERE clause
...xpression.
PS your fears seem unfounded. In this simple example at least, SQL Server is smart enough to only perform the calculation once, even though you've referenced it twice. Go ahead and compare the plans; you'll see they're identical. If you have a more complex case where you see the expressi...
How to get the top 10 values in postgresql?
...dex on score.
Starting with version 8.4, you can also use the standard (SQL:2008) fetch first
select *
from scores
order by score desc
fetch first 10 rows only
As @Raphvanns pointed out, this will give you the first 10 rows literally. To remove duplicate values, you have to select distinct r...