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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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How to disable text selection using jQuery?
Does jQuery or jQuery-UI have any functionality to disable text selection for given document elements?
13 Answers
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Efficient SQL test query or validation query that will work across all (or most) databases
...er a little bit of research along with help from some of the answers here:
SELECT 1
H2
MySQL
Microsoft SQL Server (according to NimChimpsky)
PostgreSQL
SQLite
SELECT 1 FROM DUAL
Oracle
SELECT 1 FROM any_existing_table WHERE 1=0
or
SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS
or
CALL NOW()
HS...
Best way to unselect a in jQuery?
What is the best way, using jQuery, to elegantly unselect the option?
15 Answers
15
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How do I flush the cin buffer?
... everything until EOF. (you can also supply a second argument which is the character to read until (ex: '\n' to ignore a single line).
Also: You probably want to do a: std::cin.clear(); before this too to reset the stream state.
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Is there an onSelect event or equivalent for HTML ?
I have an input form that lets me select from multiple options, and do something when the user changes the selection. Eg,
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How to declare a variable in MySQL?
...at has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BETWEEN @start AND @finish...
A quick and easy way to join array elements with a separator (the opposite of split) in Java [duplic
... We should mention that this approach works only for List<CharSequence> or CharSequence[] elements like list or arrays of Strings, StringBuilder.
– Pshemo
Apr 29 '15 at 10:36
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sed or awk: delete n lines following a pattern
...;/div>/,$d' out.txt but it gives error saying : sed: -e expression #1, char 24: extra characters after command Thanks in advance.
– N mol
Aug 24 '13 at 2:37
8
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Easy way to turn JavaScript array into comma-separated list?
...ut I need to concatenate list of IDs, no chance of commas or other special chars
– davewilliams459
Feb 8 '12 at 15:37
11
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