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What is the difference between SQL Server 2012 Express versions?
...itions you are asking about, just focus on the last three columns of every table in there.
Summary compiled from the above document:
* = contains the feature
SQLEXPR SQLEXPRWT SQLEXPRADV
---------------------------------------------------------...
Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...o use query hints, restructure the query, update statistics, use temporary tables, add indexes, and so on to get better performance.
As for your question. The performance of CTEs and subqueries should, in theory, be the same since both provide the same information to the query optimizer. One diff...
Like Operator in Entity Framework?
...note that "WHERE Name LIKE '%xyz%'" will be unable to use an index, so if table is huge it might not perform that well...
– Mitch Wheat
Jun 23 '09 at 14:49
1
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Can hash tables really be O(1)?
It seems to be common knowledge that hash tables can achieve O(1), but that has never made sense to me. Can someone please explain it? Here are two situations that come to mind:
...
How to turn on/off ReactJS 'development mode'?
...ing the minified react will leave all those potential optimizations on the table as well.
Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV !== "production")
// do propType checks...
How do I move a table into a schema in T-SQL
I want to move a table into a specific Schema using T-SQL? I am using SQL Server 2008.
2 Answers
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What is the error “Every derived table must have its own alias” in MySQL?
...
Every derived table (AKA sub-query) must indeed have an alias. I.e. each query in brackets must be given an alias (AS whatever), which can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn F...
How to Vertical align elements in a div?
...
This also works with inline-block and table-cell elements. If you are having issues with this, try adjusting line-height of the container element (i.e. context) since it is used in the vertical-align line box calculations.
– Alex W
...
Is there a way to get a collection of all the Models in your Rails app?
...
ActiveRecord::Base.connection.tables.map do |model|
model.capitalize.singularize.camelize
end
will return
["Article", "MenuItem", "Post", "ZebraStripePerson"]
Additional information If you want to call a method on the object name without model:stri...
SQL variable to hold list of integers
...
Table variable
declare @listOfIDs table (id int);
insert @listOfIDs(id) values(1),(2),(3);
select *
from TabA
where TabA.ID in (select id from @listOfIDs)
or
declare @listOfIDs varchar(1000);
SET @listOfIDs = ',1,2,3...