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How does MySQL process ORDER BY and LIMIT in a query?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ...
How to convert float to varchar in SQL Server
...
Try using the STR() function.
SELECT STR(float_field, 25, 5)
STR() Function
Another note: this pads on the left with spaces. If this is a problem combine with LTRIM:
SELECT LTRIM(STR(float_field, 25, 5))
...
Why Android Studio says “Waiting For Debugger” if am NOT debugging?
...e. Just go to "Android device"->"Settings"->"Developer Options"->"Select app to be debugged". It will likely be pointing to your application. Just select the option and then select "None".
Note: As mentioned, even if "None" is already selected, re-selecting "None" appears to correct the pr...
Implement paging (skip / take) functionality with this query
...
In SQL Server 2012 it is very very easy
SELECT col1, col2, ...
FROM ...
WHERE ...
ORDER BY -- this is a MUST there must be ORDER BY statement
-- the paging comes here
OFFSET 10 ROWS -- skip 10 rows
FETCH NEXT 10 ROWS ONLY; -- take 10 rows
If we want...
Retrieve the maximum length of a VARCHAR column in SQL Server
...
Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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How do I check how many options there are in a dropdown menu?
...
var length = $('#mySelectList').children('option').length;
or
var length = $('#mySelectList > option').length;
This assumes your <select> list has an ID of mySelectList.
http://api.jquery.com/length/
http://api.jquery.com/childr...
How to change identity column values programmatically?
...ITY(1,1) PRIMARY KEY,
X VARCHAR(10)
)
INSERT INTO Test
OUTPUT INSERTED.*
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
Then you can do
/*Define table with same structure but no IDENTITY*/
CREATE TABLE Temp
(
ID INT PRIMARY KEY,
X VARCHAR(10)
)
/*Switch table metadata to new struct...
Better techniques for trimming leading zeros in SQL Server?
...
Why don't you just cast the value to INTEGER and then back to VARCHAR?
SELECT CAST(CAST('000000000' AS INTEGER) AS VARCHAR)
--------
0
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How can I make an entire HTML form “readonly”?
...e="text" name="something" placeholder="enter some text" />
<select>
<option value="0" disabled="disabled" selected="selected">select somethihng</option>
<option value="1">woot</option>
<option value="2">is</opt...
MySQL vs MongoDB 1000 reads
...s://github.com/webcaetano/mongo-mysql
10 rows
mysql insert: 1702ms
mysql select: 11ms
mongo insert: 47ms
mongo select: 12ms
100 rows
mysql insert: 8171ms
mysql select: 10ms
mongo insert: 167ms
mongo select: 60ms
1000 rows
mysql insert: 94813ms (1.58 minutes)
mysql select: 13ms
mongo inser...