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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 exclude specific folders or files from validation in Eclipse?
...ge below)
Note: In Eclipse Indigo you have to Right click the folder and select properties and then select resource in the left navigation.
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Read data from SqlDataReader
...you use indexes like reader.GetString(0) will it use the first column you selected in your query or the firstt column on the table. I have a table with 3 columns in order: ID, Dir, Email. My command selects dir and email. Will reader.GetStrting(0) retrieve dir or ID? Are the indexes based off t...
SQL Server Output Clause into a scalar variable
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But then I'd have to "SELECT @someInt = ID FROM @ID". I wanted to know if its possible to skip that extra step (and intermediary table variable) if all I need is the resulting int.
– Benoittr
Apr 5 '11 at 21:...
What is the benefit of zerofill in MySQL?
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When you select a column with type ZEROFILL it pads the displayed value of the field with zeros up to the display width specified in the column definition. Values longer than the display width are not truncated. Note that usage of ZER...
How to create a dialog with “yes” and “no” options?
... dynamically-generated elements:
a and button clicks
form submits
option selects
jQuery:
$(document).on('click', ':not(form)[data-confirm]', function(e){
if(!confirm($(this).data('confirm'))){
e.stopImmediatePropagation();
e.preventDefault();
}
});
$(document).on('submi...
IntelliJ: Working on multiple projects
...ven Projects" window (View > Tool Windows > Maven Projects) and then select the additional pom file you want to import.
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Create code first, many to many, with additional fields in association table
...OfMembers = context.Members
.Where(m => m.LastName == "Smith")
.SelectMany(m => m.MemberComments.Select(mc => mc.Comment))
.ToList();
... or ...
var commentsOfMembers = context.MemberComments
.Where(mc => mc.Member.LastName == "Smith")
.Select(mc => mc.Comment)
...
LINQ To Entities does not recognize the method Last. Really?
...e fact that eventually it has to translate that query to SQL and SQL has a SELECT TOP (in T-SQL) but not a SELECT BOTTOM (no such thing).
There is an easy way around it though, just order descending and then do a First(), which is what you did.
EDIT:
Other providers will possibly have different im...
PostgreSQL LIKE query performance variations
... gist_trgm_ops);
Difference between GiST and GIN index
Example query:
SELECT * FROM tbl WHERE col LIKE '%foo%'; -- leading wildcard
SELECT * FROM tbl WHERE col ILIKE '%foo%'; -- works case insensitively as well
Trigrams? What about shorter strings?
Words with less than 3 letters in indexed...