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Is it possible to insert multiple rows at a time in an SQLite database?
...
This can be recast into SQLite as:
INSERT INTO 'tablename'
SELECT 'data1' AS 'column1', 'data2' AS 'column2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
a note on performance
I originally used this technique to efficiently lo...
Direct vs. Delegated - jQuery .on()
...green").on(), binds a click handler directly to the span(s) that match the selector at the moment that code is executed. This means if other spans are added later (or have their class changed to match) they have missed out and will not have a click handler. It also means if you later remove the "gre...
Ineligible Devices section appeared in Xcode 6.x.x
...6 my devices moved to greyed-out section Ineligible Devices and I can't select them as deploy target:
32 Answers
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How to select last two characters of a string
I need to select last two characters from the variable, whether it is digit or letters.
9 Answers
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How to use jQuery to select a dropdown option?
I was wondering if it’s possible to get jQuery to select an <option> , say the 4th item, in a dropdown box?
13 Ans...
clang: how to list supported target architectures?
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> llc -mattr=help
Available CPUs for this target:
amdfam10 - Select the amdfam10 processor.
athlon - Select the athlon processor.
athlon-4 - Select the athlon-4 processor.
athlon-fx - Select the athlon-fx processor.
athlon-mp - Select the athlon-mp processor...
How to convert all tables from MyISAM into InnoDB?
...database here first
//
// Actual code starts here
$sql = "SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'your_database_name'
AND ENGINE = 'MyISAM'";
$rs = mysql_query($sql);
while($row = mysql_fetch_array($rs))
{
$tbl = ...
Generate MD5 hash string with T-SQL
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Use HashBytes
SELECT HashBytes('MD5', 'email@dot.com')
That will give you 0xF53BD08920E5D25809DF2563EF9C52B6
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SELECT CONVERT(NVARCHAR(32),HashBytes('MD5', 'email@dot.com'),2)
That will give you F53BD08920E5D25809DF2563EF9C52B6
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Ordering by the order of values in a SQL IN() clause
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Use MySQL's FIELD() function:
SELECT name, description, ...
FROM ...
WHERE id IN([ids, any order])
ORDER BY FIELD(id, [ids in order])
FIELD() will return the index of the first parameter that is equal to the first parameter (other than the first paramet...
Query for array elements inside JSON type
...src":"bar.png"}]
, "background":"background.png"}'::json)
)
SELECT *
FROM reports r, json_array_elements(r.data#>'{objects}') obj
WHERE obj->>'src' = 'foo.png';
The CTE (WITH query) just substitutes for a table reports.
Or, equivalent for just a single level of nesting:
SE...
