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MySQL COUNT DISTINCT
...
Select
Count(Distinct user_id) As countUsers
, Count(site_id) As countVisits
, site_id As site
From cp_visits
Where ts >= DATE_SUB(NOW(), INTERVAL 1 DAY)
Group By site_id
...
PostgreSQL Autoincrement
...RT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter SERIAL onto an existing column.
sha...
Cannot issue data manipulation statements with executeQuery()
...() to issue data manipulation statements. executeQuery() is only meant for SELECT queries (i.e. queries that return a result set).
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Any tips on how to organize Eclipse environment on multiple monitors?
...s don't "communicate", e.g. javadoc view in one window won't be updated by selections in the other, similarly jUnit.
– David
Nov 2 '11 at 15:01
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Eclipse JPA Project Change Event Handler (waiting)
...ould probably try to open a discussion on the amount of included and not deselectable features/project included in a release. And it should maybe discuss ways to disable packaged features (such as JPT).
– mwhs
Mar 31 '14 at 8:38
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Does order of where clauses matter in SQL?
...rstName) (or both)
On the other hand - again for SQL Server - if you use SELECT * to grab all columns from a table, and the table is rather small, then there's a good chance the query optimizer will just do a table (or clustered index) scan instead of using an index (because the lookup into the fu...
Convert List into Comma-Separated String
...s before you Aggragate to string. So you can do something like this: list.Select(x => string.Format("{0}:{1}", x.Key, x.Value)).Aggregate((a, x) => a+ ", " + x);
– bets
Jul 20 '17 at 8:14
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Cannot create or edit Android Virtual Devices (AVD) from Eclipse, ADT 22.6
...lone button worked and I was able to successfully edit the clone.
Steps:
Select a Device by Google
Click the "Clone..." button
A window will pop up, click "Clone device"
Select the newly cloned Device, it should say "... by User"
Click the "Edit" button on the side
There you have it...
What do querySelectorAll and getElementsBy* methods return?
...sByClassName (and similar functions like getElementsByTagName and querySelectorAll ) work the same as getElementById or do they return an array of elements?
...
How to import an excel file in to a MySQL database
...r Excel table into the sales table of a MySQL database named mydatabase.
Select the relevant cells:
Paste into Mr. Data Converter and select the output as MySQL:
Change the table name and column definitions to fit your requirements in the generated output:
CREATE TABLE sales (
id INT NOT N...