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Improve INSERT-per-second performance of SQLite
...f possible, which will replace the implied unique row number column in the table.
If you are using multiple threads, you can try using the shared page cache, which will allow loaded pages to be shared between threads, which can avoid expensive I/O calls.
Don't use !feof(file)!
I've also asked simi...
Using backticks around field names
...r field` , `field,with,comma`
Which does of course generate badly named tables.
If you're just being concise I don't see a problem with it,
you'll note if you run your query as such
EXPLAIN EXTENDED Select foo,bar,baz
The generated warning that comes back will have back-ticks and fully qua...
How to use GROUP BY to concatenate strings in SQL Server?
...5 and later. Original question didn't specify the version in use.]
CREATE TABLE #YourTable ([ID] INT, [Name] CHAR(1), [Value] INT)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (1,'A',4)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (1,'B',8)
INSERT INTO #YourTable ([ID],[Name],[Value]...
NOT IN vs NOT EXISTS
...OT IN sub query were to return no results at all (i.e. the [Order Details] table is empty). In which case it should. In the plan for my sample data this is implemented by adding another anti semi join as below.
The effect of this is shown in the blog post already linked by Buckley. In the example...
What's the best way to store co-ordinates (longitude/latitude, from Google Maps) in SQL Server?
I'm designing a table in SQL Server 2008 that will store a list of users and a Google Maps co-ordinate (longitude & latitude).
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Getting list of lists into pandas DataFrame
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Call the pd.DataFrame constructor directly:
df = pd.DataFrame(table, columns=headers)
df
Heading1 Heading2
0 1 2
1 3 4
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PHP code to convert a MySQL query to CSV [closed]
...MINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $select ) or die ( "Sql error : " . mysql_error( ) );
$fi...
How do I set a background-color for the width of text, not the width of the entire element, using CS
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display:table is a better choice... to avoid the problem highlighted in the comments section in the next reply. display:inline will concatenate <h1> and <h2> to be in same line.... when they are originally in next lines.
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Best way to center a on a page vertically and horizontally? [duplicate]
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@FlashThunder you suggest tables for non-table data, aren't you?
– Vladimir Starkov
Jan 10 '15 at 3:17
1
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What are .dex files in Android?
...lication code file.
Android programs are compiled into .dex (Dalvik Executable) files, which are in turn zipped into a single .apk file on the device. .dex files can be created by automatically translating compiled applications written in the Java programming language.
Dex file format:
1. File ...