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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 ...
What does it mean by select 1 from table?
...
SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, c...
postgresql return 0 if returned value is null
...eved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan
WHERE listing_Type = 'AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - ...
How to find the size of localStorage
...ntil DevTools are opened)
Opera 12.15 ~4212ms /3.55Mb (this is when 5Mb is selected, but Opera asks nicely if we want increase the amount of lS, unfortunately it crashes if test conducted a few times in a row)
Win 8 (Under Parallels 8)
IE10 ~7850ms /9.54Mb
...
How to see query history in SQL Server Management Studio
...been evicted, etc.), you may be able to find the query in the plan cache.
SELECT t.[text]
FROM sys.dm_exec_cached_plans AS p
CROSS APPLY sys.dm_exec_sql_text(p.plan_handle) AS t
WHERE t.[text] LIKE N'%something unique about your query%';
If you lost the file because Management Studio crashed, you...
What does “@private” mean in Objective-C?
...lic
int publicNumber;
@protected // Protected is the default
char protectedLetter;
@private
BOOL privateBool;
}
@end
@implementation MyFirstClass
- (id)init {
if (self = [super init]) {
publicNumber = 3;
protectedLetter = 'Q';
privateBool = NO;
...
NOT IN vs NOT EXISTS
...llow NULLs the NOT IN will be treated identically to the following query.
SELECT ProductID,
ProductName
FROM Products p
WHERE NOT EXISTS (SELECT *
FROM [Order Details] od
WHERE p.ProductId = od.ProductId)
The exact plan may vary but for my examp...
Select top 10 records for each category
...
If you are using SQL 2005 you can do something like this...
SELECT rs.Field1,rs.Field2
FROM (
SELECT Field1,Field2, Rank()
over (Partition BY Section
ORDER BY RankCriteria DESC ) AS Rank
FROM table
) rs WHERE Rank <= 10
If y...
Converting between strings and ArrayBuffers
...nterface represents an encoder for a specific method,
that is a specific character encoding, like utf-8, iso-8859-2, koi8,
cp1261, gbk, ... An encoder takes a stream of code points as input and
emits a stream of bytes.
Change note since the above was written: (ibid.)
Note: Firefox, Chrom...
Removing an item from a select box
How do I remove items from, or add items to, a select box? I'm running jQuery, should that make the task easier. Below is an example select box.
...