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How to check for Is not Null And Is not Empty string in SQL server?
... ('A'),
(''),
(' '),
(NULL);
SELECT *
FROM T
WHERE C <> ''
Returns just the single row A. I.e. The rows with NULL or an empty string or a string consisting entirely of spaces are all excluded by this query.
SQL Fiddle
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Is the NOLOCK (Sql Server hint) bad practice?
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With NOLOCK hint, the transaction isolation level for the SELECT statement is READ UNCOMMITTED. This means that the query may see dirty and inconsistent data.
This is not a good idea to apply as a rule. Even if this dirty read behavior is OK for your mission critical web based app...
How do I disable text selection with CSS or JavaScript? [duplicate]
...
<div
style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;"
unselectable="on"
onselectstart="return false;"
onmousedown="return false;">
Blabla
</div>
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How can I resolve “Error: No developer directory found at /Developer”?
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sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
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how to convert a string to date in mysql?
I have a string column which acts as a date and I want to select it as a date .
5 Answers
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What is a stored procedure?
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CREATE PROCEDURE Users_GetUserInfo
@login nvarchar(30)=null
AS
SELECT * from [Users]
WHERE ISNULL(@login,login)=login
A benefit of stored procedures is that you can centralize data access logic into a single place that is then easy for DBA's to optimize. Stored procedures also have...
View HTTP headers in Google Chrome?
...you don't see any resources - look at tabs area (All | XHR JS and etc) and select All
– Zanshin13
Jan 12 '17 at 10:05
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Naming of ID columns in database tables
...!)and forget to change the alias in the join condition.
So you now have
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1.id = t2.table1id
join table3 t3 on t1.id = t3.table2id
when you meant
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1...
Use '=' or LIKE to compare strings in SQL?
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To see the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is muc...
Xcode is not currently available from the Software Update server
...e Xcode command line tools is pointed correctly using this command
xcode-select -p
Which might show some path like
/Applications/Xcode.app/Contents/Developer
Change the path to correct path using the switch command
xcode-select --switch /Library/Developer/CommandLineTools/
this should...