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Query to count the number of tables I have in MySQL
...t to do a quick command line query to count the number of tables in my database. Is that possible? If so, what is the query?
...
Get index of selected option with jQuery
...mj: Then you are doing something wrong. The selectedIndex property is zero based. I checked the documentation and even tried it myself to be truly 100% sure about this.
– Guffa
Mar 26 '16 at 23:24
...
Difference between natural join and inner join
...t specify the joining columns in a natural join; the join is strictly name-based. See also Wikipedia.)
(There's a cheat in the inner join output; the a. and b. parts would not be in the column names; you'd just have column1, column2, column1, column3 as the headings.)
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What is the fastest substring search algorithm?
...ute force may win.
Edit:
A different algorithm might be best for finding base pairs, english phrases, or single words. If there were one best algorithm for all inputs, it would have been publicized.
Think about the following little table. Each question mark might have a different best search al...
Java `final` method: what does it promise?
...You can't override it in your derived class, therefore it will do what the base class author intended.
http://download.oracle.com/javase/tutorial/java/IandI/final.html
Worth noting is the part where it suggests that methods called from constructors should be final.
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Change Placeholder Text using jQuery
.... Use parseInt($(this).val(), 10) or check for '1'. The ten is to denote base 10.
$(function () {
$('input[placeholder], textarea[placeholder]').blur();
$('#serMemdd').change(function () {
var k = $(this).val();
if (k == '1') {
$("#serMemtb").attr("placeholder"...
Linq to Entities join vs groupjoin
... input sequence, found all the matching items from the "inner" sequence
(based on a key projection on each sequence) and then yielded pairs of
matching elements. GroupJoin is similar, except that instead of
yielding pairs of elements, it yields a single result for each "outer"
item based on ...
Storing time-series data, relational or non?
...n is never a Key (duplicate rows, which are prohibited in a Relational database, must be prevented by other means).
The Id column requires an additional Index, which obviously impedes the speed of INSERT/DELETE, and adds to the disk space used.
You can get rid of it. Please.
Elevation
Now ...
Is a view faster than a simple query?
...t is materialized immediately and persisted in physical storage in the database, saving the overhead of performing this costly operation at execution time.
Second, these indexed views can work even when they are not directly referenced by another query as the optimizer will use them in place of a ...
How to get error information when HttpWebRequest.GetResponse() fails
... wraps HttpWebRequest and Response into simple methods that return objects based on the results. It uses some of the techniques described in these answers and has plenty of code inspired by answers from this and similar threads. It automatically catches any exceptions, seeks to abstract as much bo...