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Is there a performance gain in using single quotes vs double quotes in ruby?
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The measured differences are not meaningful. Just the order (because of garbage collection) can make important a difference. There is no runtime difference between ' and " as they are parsed to the same thing.
– Marc-André Lafortune
Aug 1 ...
How to include file in a bash shell script
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In my situation, in order to include color.sh from the same directory in init.sh, I had to do something as follows.
. ./color.sh
Not sure why the ./ and not color.sh directly. The content of color.sh is as follows.
RED=`tput setaf 1`
GREEN=...
How to evaluate a math expression given in string form?
...described wiki.The logic of this algoritm starting from rules of operation orders. 1. operator sign | variable evaluation | function call | parenthesis (sub-expressions); 2. exponentiation; 3. multiplication, division; 4. addition, subtraction;
– Vasile Bors
J...
Only parameterless constructors and initializers are supported in LINQ to Entities
...u're building, there is another way to solve this issue.
var query = from orderDetail in context.OrderDetails
join order in context.Orders on order.OrderId equals orderDetail.orderId
select new { order, orderDetail };
At this point you have an IQueryable containing an anon...
Is it possible to Pivot data using LINQ?
...lect(g => new {
CustId = g.Key,
Jan = g.Where(c => c.OrderDate.Month == 1).Sum(c => c.Qty),
Feb = g.Where(c => c.OrderDate.Month == 2).Sum(c => c.Qty),
March = g.Where(c => c.OrderDate.Month == 3).Sum(c => c.Qty)
});
GroupBy in Linq does not...
When to use DataContract and DataMember attributes?
...non-public properties or fields
without [DataMember], you cannot define an order of serialization (Order=) and the DCS will serialize all properties alphabetically
without [DataMember], you cannot define a different name for your property (Name=)
without [DataMember], you cannot define things like I...
Android, ListView IllegalStateException: “The content of the adapter has changed but ListView did no
...xtView and I am facing the same problem...Could you advise me something in order to resolve?
– tonix
May 3 '14 at 20:32
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Using multiple property files (via PropertyPlaceholderConfigurer) in multiple projects/modules
...der location="classpath*:connection.properties" ignore-unresolvable="true" order="1" />
<context:property-placeholder location="classpath*:general.properties" order="2"/>
In case multiple elements are present in the
Spring context, there are a few best practices that should be
fo...
How to select date without time in SQL
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I have same error when i use select convert (table.order_date , getdate()); sql server version 2017 , the error (Type date is not a defined system type) the column type datetime
– Abdullah
May 27 at 11:43
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The multi-part identifier could not be bound
...GROUP BY maxa
) AS dkcd ON dkcd.maxa = a.maxa
WHERE a.maxa <> '99'
ORDER BY a.maxa
Here the tables a and b are joined first, then the result is joined to dkcd. Basically, this is the same query as yours, only using a different syntax for one of the joins, which makes a great difference: th...