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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), ...
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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Submit jQuery UI dialog on
...neat, in Firefox 7.0.1 this will also trigger your "OK" button if the user selects something from the autocomplete drop down box, e.g. a previously entered email address.
– cburgmer
Mar 11 '12 at 9:49
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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...
How do I auto-submit an upload form when a file is selected?
...le upload form. How do I make it submit automatically when a file has been selected? I don't want the user to have to click the Submit button.
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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 to easily initialize a list of Tuples?
..." }, new Hold { Id = 2, Name = "You" } };
var anonymousProjections = holds.Select(x => new { SomeNewId = x.Id, SomeNewName = x.Name });
var namedTuples = holds.Select(x => (TupleId: x.Id, TupleName: x.Name));
Reuse the tuples later with grouping methods or use a method to construct the...
How to manually trigger validation with jQuery validate?
... i have query like this if ($('#myElem').val()=='2017-4-12'){ date selection wrong }else{ valid selection}
– srinivas gowda
Apr 12 '17 at 9:51
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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...
How to take backup of a single table in a MySQL database?
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You can use easily to dump selected tables using MYSQLWorkbench tool ,individually or group of tables at one dump then import it as follow: also u can add host information if u are running it in your local by adding -h IP.ADDRESS.NUMBER after-u usernam...