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What does SQL clause “GROUP BY 1” mean?
...d name, you may also group by ordinal, or position of the field within the table. 1 corresponds to the first field (regardless of name), 2 is the second, and so on.
This is generally ill-advised if you're grouping on something specific, since the table/view structure may change. Additionally, it ma...
MySQL show current connection info
...7 min 16 sec
Threads: 1 Questions: 21 Slow queries: 0 Opens: 33 Flush tables: 1 Open tables: 26 Queries per second avg: 0.48
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mysql>
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Tricks to manage the available memory in an R session
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I use the data.table package. With its := operator you can :
Add columns by reference
Modify subsets of existing columns by reference, and by group by reference
Delete columns by reference
None of these operations copy the (potentially...
Is storing a delimited list in a database column really that bad?
...m in a comma separated list of values stored in one column of the database table.
10 Answers
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What is the difference between varchar and varchar2 in Oracle?
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Taken from the latest stable Oracle production version 12.2:
Data Types
The major difference is that VARCHAR2 is an internal data type and VARCHAR is an external data type. So we need to understand the difference between an internal and external ...
Naming convention for unique constraint
...rimary key and foreign key have commonly used and obvious conventions ( PK_Table and FK_Table_ReferencedTable , respectively). The IX_Table_Column naming for indexes is also fairly standard.
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Fast permutation -> number -> permutation mapping algorithms
... brought down to n*log(n), see section 10.1.1
("The Lehmer code (inversion table)", p.232ff) of the fxtbook:
http://www.jjj.de/fxt/#fxtbook
skip to section 10.1.1.1 ("Computation with large arrays" p.235) for the fast method.
The (GPLed, C++) code is on the same web page.
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How can I edit a view using phpMyAdmin 3.2.4?
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In your database table list it should show View in Type column.
To edit View:
Click on your View in table list
Click on Structure tab
Click on Edit View under Check All
Hope this help
update: in PHPMyAdmin 4.x, it doesn't show View in ...
Row Offset in SQL Server
... SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable
WHERE MyDerivedTable.RowNum BETWEEN @startRow AND @endRow
SQL Server 2000
Efficiently Paging Through Large Result Sets in SQL Server 2000
A More Efficient Method for Paging Through Large Result S...
SQL - using alias in Group By
...M (
SELECT ItemName, SUBSTRING(ItemName, 1, 1) AS FirstLetter
FROM table1
) ItemNames
GROUP BY ItemName, FirstLetter
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