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Difference between fmt.Println() and println() in Go
...n built into the language. It is in the Bootstrapping section of the spec. From the link:
Current implementations provide several built-in functions useful
during bootstrapping. These functions are documented for completeness
but are not guaranteed to stay in the language. They do not retu...
Best way to select random rows PostgreSQL
I want a random selection of rows in PostgreSQL, I tried this:
12 Answers
12
...
MySQL SELECT only not null values
Is it possible to do a select statement that takes only NOT NULL values?
9 Answers
9
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sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...
Is there an equivalent to CTRL+C in IPython Notebook in Firefox to break cells that are running?
...thing that is running in iPython Notebook and you started iPython Notebook from a terminal, you can hit CTRL+C twice in that terminal to interrupt the entire iPython Notebook server. This will stop iPython Notebook alltogether, which means it won't be possible to restart or save your work, so this i...
Difference between EXISTS and IN in SQL?
...way to avoid counting:
--this statement needs to check the entire table
select count(*) from [table] where ...
--this statement is true as soon as one match is found
exists ( select * from [table] where ... )
This is most useful where you have if conditional statements, as exists can be a lot ...
How to order by with union in SQL?
Is it possible to order when the data is come from many select and union it together? Such as
8 Answers
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How to find third or nth maximum salary from salary table?
...you want a single) or DENSE_RANK(for all related rows):
WITH CTE AS
(
SELECT EmpID, EmpName, EmpSalary,
RN = ROW_NUMBER() OVER (ORDER BY EmpSalary DESC)
FROM dbo.Salary
)
SELECT EmpID, EmpName, EmpSalary
FROM CTE
WHERE RN = @NthRow
...
Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
...
dd: How to calculate optimal blocksize? [closed]
... pretty solid history of being reliably performant: You can find a message from the Eug-Lug mailing list, circa 2002, recommending a block size of 64K here: http://www.mail-archive.com/eug-lug@efn.org/msg12073.html
For determining THE optimal output block size, I've written the following script tha...