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mysql - how many columns is too many?
...every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name the columns you need.
As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entit...
Database Design for Tagging
... to rebuilt every time a question has a tag added or removed. A query like select * from question q inner join question_has_tag qt where tag_id in (select tag_id from tags where (what we want) minus select tag_id from tags where (what we don't) should be fine and scale out assuming the right b-tree ...
MySQL: Invalid use of group function
..., not WHERE.
The difference is: the WHERE clause filters which rows MySQL selects. Then MySQL groups the rows together and aggregates the numbers for your COUNT function.
HAVING is like WHERE, only it happens after the COUNT value has been computed, so it'll work as you expect. Rewrite your subque...
How can I check whether a option already exist in select by JQuery
How can I check whether a option already exist in select by JQuery?
8 Answers
8
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Navigation bar appear over the views with new iOS7 SDK
...ar takes up should be accounted for automatically
if ([self respondsToSelector:@selector(edgesForExtendedLayout)])
self.edgesForExtendedLayout = UIRectEdgeNone;
You need add the above in your -(void)viewDidLoad method.
Note: You should be using the latest GM release of iOS 7 and Xcode 5 ...
How to combine class and ID in CSS selector?
...is is super old and people keep finding it: don't use the tagNames in your selectors. #content.myClass is faster than div#content.myClass because the tagName adds a filtering step that you don't need. Use tagNames in selectors only where you must!
...
Resolving LNK4098: defaultlib 'MSVCRT' conflicts with
...ry time I want to create an application in VC++.
Right-click the project, select Properties then under 'Configuration properties | C/C++ | Code Generation', select "Multi-threaded Debug (/MTd)" for Debug configuration.
Note that this does not change the setting for your Release configuration - you...
iTerm2 keyboard shortcut - split pane navigation
...erences -> Profiles/<Your Profile>/Keys). There you have actions "Select Split Pane Above", "Select Split Pane Below", "Above" "Down".
– Sundar
Aug 11 '18 at 19:07
ad...
MySQL: How to copy rows, but change a few fields?
...able
( Event_ID
, col2
...
)
SELECT "155"
, col2
...
FROM Table WHERE Event_ID = "120"
Here, the col2, ... represent the remaining columns (the ones other than Event_ID) in your table.
...
Why do I get “Procedure expects parameter '@statement' of type 'ntext/nchar/nvarchar'.” when I try t
...r because @SQL needs to be NVARCHAR
DECLARE @SQL VARCHAR(100)
SET @SQL = 'SELECT TOP 1 * FROM sys.tables'
EXECUTE sp_executesql @SQL
So:
DECLARE @SQL NVARCHAR(100)
SET @SQL = 'SELECT TOP 1 * FROM sys.tables'
EXECUTE sp_executesql @SQL
...