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What does SQL clause “GROUP BY 1” mean?
...d name, you may also group by ordinal, or position of the field within the table. 1 corresponds to the first field (regardless of name), 2 is the second, and so on.
This is generally ill-advised if you're grouping on something specific, since the table/view structure may change. Additionally, it ma...
What does multicore assembly language look like?
.... All that's needed is software support for each thread to set up its own tables and messaging queues. The OS uses those to do the actual multi-threaded scheduling.
As far as the actual assembly is concerned, as Nicholas wrote, there's no difference between the assemblies for a single threaded or...
Reducing the space between sections of the UITableView
Is there a way to reduce the space between two sections of a UITableView? There are about 15 pixels between every single section I have. I did already try to return 0 for -tableView:heightForFooterInSection: and -tableView:heightForHeaderInSection: but that doesn't change anything.
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Rails 3 migrations: Adding reference column?
...class AddUserToTester < ActiveRecord::Migration
def change
change_table :testers do |t|
t.references :user, index: true
end
end
def down
change_table :testers do |t|
t.remove :user_id
end
end
end
c.f.: http://apidock.com/rails/ActiveRecord/ConnectionAdapters...
How to set the UITableView Section title programmatically (iPhone/iPad)?
I've created a UITableView in Interface Builder using storyboards . The UITableView is setup with static cells and a number of different sections.
...
SELECT * WHERE NOT EXISTS
...
You didn't join the table in your query.
Your original query will always return nothing unless there are no records at all in eotm_dyn, in which case it will return everything.
Assuming these tables should be joined on employeeID, use the foll...
How to add a footer to a UITableView in Storyboard
...
You can just drag a view to the bottom area of the tableView. You'll see in the hierarchy that it will be a subview of the tableview. You can then drag subviews such as labels and buttons there, adjust the height, etc.
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How can I edit a view using phpMyAdmin 3.2.4?
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In your database table list it should show View in Type column.
To edit View:
Click on your View in table list
Click on Structure tab
Click on Edit View under Check All
Hope this help
update: in PHPMyAdmin 4.x, it doesn't show View in ...
What is PAGEIOLATCH_SH wait type in SQL Server?
...stem.
In practice, this almost always happens due to large scans over big tables. It almost never happens in queries that use indexes efficiently.
If your query is like this:
Select * from <table> where <col1> = <value> order by <PrimaryKey>
, check that you have a composit...
Versioning SQL Server database
...N to N+1. (These go in your version control system.) A _version_history_ table, something like
create table VersionHistory (
Version int primary key,
UpgradeStart datetime not null,
UpgradeEnd datetime
);
gets a new entry every time an upgrade script runs which corresponds to th...