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Recommended SQL database design for tags or tagging [closed]
...ries which you will do: Output all Tags for one Item, draw a Tag-Cloud and select all items for one Tag Title.
All Tags for one Item:
3-Table:
SELECT Tag.Title
FROM Tag
JOIN ItemTag ON Tag.TagID = ItemTag.TagID
WHERE ItemTag.ItemID = :id
2-Table:
SELECT Tag.Title
FROM Tag
WHERE Tag.Item...
Correct way to remove plugin from Eclipse
...from Eclipse/STS :
Go to install folder of eclipse ----> plugin --> select required plugin and remove it.
Ex-
Step 1.
E:\springsource\sts-3.4.0.RELEASE\plugins
Step 2.
select and remove related plugins jars.
sh...
MySQL - force not to use cache for testing speed of query
...ACHE (MySQL 5.7) option in your query.
(MySQL 5.6 users click HERE )
eg.
SELECT SQL_NO_CACHE * FROM TABLE
This will stop MySQL caching the results, however be aware that other OS and disk caches may also impact performance. These are harder to get around.
...
How to detect total available/free disk space on the iPhone/iPad device?
...
Converting to a float may give inaccurate results above around 2GB. If you need to deal with really large file sizes, use a double or long double instead.
– Ash
Feb 3 '12 at 10:16
...
HTTPS connections over proxy servers
...can remember, you need to use a HTTP CONNECT query on the proxy. this will convert the request connection to a transparent TCP/IP tunnel.
so you need to know if the proxy server you use support this protocol.
share
...
Set cache-control for entire S3 bucket automatically (using bucket policies?)
...it can take some time.
Log in to AWS Management Console
Go into S3 bucket
Select all files by route
Choose "More" from the menu
Select "Change metadata"
In the "Key" field, select "Cache-Control" from the drop down menu
max-age=604800Enter (7 days) for Value
Press "Save" button
(thanks to @biplob ...
JPA eager fetch does not join
...
JPA doesn't provide any specification on mapping annotations to select fetch strategy. In general, related entities can be fetched in any one of the ways given below
SELECT => one query for root entities + one query for related mapped entity/collection of each root entity = (n+1) que...
Getting result of dynamic SQL into a variable for sql-server
... varchar(75)
declare @counts int
SET @city = 'New York'
SET @sqlCommand = 'SELECT @cnt=COUNT(*) FROM customers WHERE City = @city'
EXECUTE sp_executesql @sqlCommand, N'@city nvarchar(75),@cnt int OUTPUT', @city = @city, @cnt=@counts OUTPUT
select @counts as Counts
...
How do I check in SQLite whether a table exists?
...sed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FROM sqlite_master WHERE type='table' AND name='{table_name}';
Where {table_name} is the name of the table to check.
Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database S...
JSON encode MySQL results
...
$sth = mysqli_query($conn, "SELECT ...");
$rows = array();
while($r = mysqli_fetch_assoc($sth)) {
$rows[] = $r;
}
print json_encode($rows);
The function json_encode needs PHP >= 5.2 and the php-json package - as mentioned here
NOTE: mysql is dep...