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Querying data by joining two tables in two database on different servers
...just prefixing the database name with the other server. I.E:
-- FROM DB1
SELECT *
FROM [MyDatabaseOnDB1].[dbo].[MyTable] tab1
INNER JOIN [DB2].[MyDatabaseOnDB2].[dbo].[MyOtherTable] tab2
ON tab1.ID = tab2.ID
Once the link is established, you can also use OPENQUERY to execute a SQL st...
Explicit vs implicit SQL joins
...e joined and how they are joined. Try compare larger SQL queries where you selecting from 8 different tables and you have lots of filtering in the where. By using join syntax you separate out the parts where the tables are joined, to the part where you are filtering the rows.
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LINQ - Left Join, Group By, and Count
...into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.ParentId into grouped
select new { ParentId = grouped.Key, Count = grouped.Count(t=>t.ChildId != null) }
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Is there any performance gain in indexing a boolean field?
...
It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
How to change the Eclipse default workspace?
...down>Workspaces.
There you can set a flag to make Eclipse prompt you to select a workspace at startup by checking the "Prompt for workspace at startup" checkbox.
You can set the number of previous workspaces to remember also. Finally there is a list of recent workspaces. If you just remove all b...
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...
Set database from SINGLE USER mode to MULTI USER
...onnected to it” might be SQL Server Management Studio window itself. Try selecting the master database and running the ALTER query again.
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How do I enumerate through a JObject?
.... I.e. you ((IEnumerable<KeyValuePair<string, JToken>>)obj).Select(...) instead of plain-old obj.Select(...); or at least that's what I found it one part of my code.
– Adrian Ratnapala
Nov 26 '14 at 9:26
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F12 no longer works in Visual Studio
...: Resharper > Options > Environment > Keyboard & Menus > (Select Visual Studio under Keyboard Shortcuts) > Apply Scheme > Save
– Rahul R.
Jun 3 '14 at 9:29
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Select elements by attribute in CSS
Is it possible to select elements in CSS by their HTML5 data attributes (for example, data-role )?
5 Answers
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