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django models selecting single field
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thanks for the answer, what if I want to select only 1 or more fields (not all)?
– zentenk
Sep 21 '11 at 16:42
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“A lambda expression with a statement body cannot be converted to an expression tree”
...SQL to be executed against the database.
Try this
Arr[] myArray = objects.Select(o => new Obj() {
Var1 = o.someVar,
Var2 = o.var2
}).ToArray();
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What is the best collation to use for MySQL with PHP? [closed]
...ng utf8_general_ci.
MySQL will not distinguish between some characters in select statements, if the utf8_general_ci collation is used. This can lead to very nasty bugs - especially for example, where usernames are involved. Depending on the implementation that uses the database tables, this problem...
How to configure Visual Studio to use Beyond Compare
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In Visual Studio, go to the Tools menu, select Options, expand Source Control, (In a TFS environment, click Visual Studio Team Foundation Server), and click on the Configure User Tools button.
Click the Add button.
Enter/select the following options for Compar...
Should you choose the MONEY or DECIMAL(x,y) datatypes in SQL Server?
...@num2 DECIMAL(19,4),
@num3 DECIMAL(19,4),
@num4 DECIMAL(19,4)
SELECT
@mon1 = 100, @mon2 = 339, @mon3 = 10000,
@num1 = 100, @num2 = 339, @num3 = 10000
SET @mon4 = @mon1/@mon2*@mon3
SET @num4 = @num1/@num2*@num3
SELECT @mon4 AS moneyresult,
@num4 AS numericresult...
Linq: GroupBy, Sum and Count
...a" is coming from, but the problem in the console app is that you're using SelectMany to look at each item in each group.
I think you just want:
List<ResultLine> result = Lines
.GroupBy(l => l.ProductCode)
.Select(cl => new ResultLine
{
ProductName =...
Find index of last occurrence of a sub-string using T-SQL
...X, followed again by REVERSE to restore the original order. For instance:
SELECT
mf.name
,mf.physical_name
,reverse(left(reverse(physical_name), charindex('\', reverse(physical_name)) -1))
from sys.master_files mf
shows how to extract the actual database file names from from their "physic...
Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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Insert text into textarea with jQuery
...aret: function(myValue){
return this.each(function(i) {
if (document.selection) {
//For browsers like Internet Explorer
this.focus();
var sel = document.selection.createRange();
sel.text = myValue;
this.focus();
}
else if (this.selectionStart || this.selec...
Extracting specific columns in numpy array
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I assume you wanted columns 1 and 9?
To select multiple columns at once, use
X = data[:, [1, 9]]
To select one at a time, use
x, y = data[:, 1], data[:, 9]
With names:
data[:, ['Column Name1','Column Name2']]
You can get the names from data.dtype.names…
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