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How do I copy items from list to list without foreach?
...single property to another list is needed:
targetList.AddRange(sourceList.Select(i => i.NeededProperty));
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Reference - What does this error mean in PHP?
...
mysql_fetch_array() expects parameter 1 to be resource, boolean given in select
All "mysql_fetch_array() expects parameter 1 to be resource, boolean given" Questions on Stackoverflow
Related Errors:
Warning: [function] expects parameter 1 to be resource, boolean given
Other mysql* functions ...
How to safely upgrade an Amazon EC2 instance from t1.micro to large? [closed]
...es" and create a Snapshot of your instance's volume.
Go to "Snapshots" and select "Create Image from Snapshot".
Go to "AMIs" and select "Launch Instance" and choose your "Instance Type" etc.
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Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
Does the order of LINQ functions matter?
... order by ((record.Score1 + record.Score2) / 2) descending
select new
{
Name = record.Name,
Average = ((record.Score1 + record.Score2) / 2)
};
If, for whatever reason, you decided to "optimize" the ...
Maximum number of records in a MySQL database table
...g with multiple billions of entries? (which would probably just make your select statements melt down long before then)
– Kzqai
Apr 26 '10 at 19:35
2
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AppSettings get value from .config file
...iguration
Go to your Solution Explorer and right click on References and select Add reference. Select the Assemblies tab and search for Configuration.
Here is an example of my App.config:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<suppo...
Get “Value” property in IGrouping
...
For any selected group,you could call
var selectedGroupValues=selectedGroup.SelectMany(x=>x);
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Where to find “Microsoft.VisualStudio.TestTools.UnitTesting” missing dll?
...ssional or above; .NET Framework 4.0).
or right click on your project and select: Add Reference... > .NET:
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How to add “on delete cascade” constraints?
...hy until you see "Constraints"), or you can query the information schema.
select *
from information_schema.key_column_usage
where position_in_unique_constraint is not null
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