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In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
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Remove border radius from Select tag in bootstrap 3
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Working example: https://jsfiddle.net/gs2q1c7p/
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background-positio...
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The value is onl...
How to check which locks are held on a table
...pful to you.
You can check which statements are blocked by running this:
select cmd,* from sys.sysprocesses
where blocked > 0
It will also tell you what each block is waiting on. So you can trace that all the way up to see which statement caused the first block that caused the other blocks.
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Using Regex to generate Strings rather than match them
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I am not sure Xeger is that good. It cannot handle character classes. It fails to recognize a simple [\w]. A look at the last line of their wiki tells us that.
– John Red
Feb 13 '17 at 12:38
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T-SQL query to show table definition?
...n get most of the details from Information Schema Views and System Views.
SELECT ORDINAL_POSITION, COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH
, IS_NULLABLE
FROM INFORMATION_SCHEMA.COLUMNS
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ReactJS Two components communicating
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manage active routes, selected tabs, spinners, pagination controls,
and so on.
Managing this ever-changing state is hard. If a model can update
another model, then a view can update a model, which updates another
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I would like to retrieve the last file inserted into my table. I know that the method first() exists and provides you with the first file in the table but I don't know how to get the last insert.
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When to use SELECT … FOR UPDATE?
Please help me understand the use-case behind SELECT ... FOR UPDATE .
2 Answers
2
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What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
... then the result is the first column of the first row. An example might be SELECT @@IDENTITY AS 'Identity'.
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ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE...