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How do I select a random value from an enumeration?
Given an arbitrary enumeration in C#, how do I select a random value?
9 Answers
9
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Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
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Inner join vs Where
... for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FROM table1 t1
INNER JOIN table2 t2 ON t1.id = t2.id;
SELECT *
FROM TABLE (DBMS_XPLAN.DISPLAY);
-- 0 select statement
-- 1 hash join (access("T1"."ID"="T2"."ID"))
-- 2 table access full table1
-- 3 table access ful...
How do I use the CONCAT function in SQL Server 2008 R2?
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You can use SELECT {fn concat ('foo', 'bar')}; in previous versions. Only accepts 2 parameters though.
– Martin Smith
May 11 '12 at 11:22
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Make Visual Studio understand CamelCase when hitting Ctrl and cursor keys
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Is there an option, to select the whole word, even if CameHumps is on? At the moment I have to press right or left several times to select a word. I hope you get me.
– Ozkan
Oct 7 '16 at 14:01
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Boolean Field in Oracle
...ate the many Boolean-like
flags that Oracle's data dictionary views use, selecting 'Y' for true
and 'N' for false. However, to interact correctly with host
environments, such as JDBC, OCCI, and other programming environments,
it's better to select 0 for false and 1 for true so it can work
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Join between tables in two different databases?
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Yes, assuming the account has appropriate permissions you can use:
SELECT <...>
FROM A.table1 t1 JOIN B.table2 t2 ON t2.column2 = t1.column1;
You just need to prefix the table reference with the name of the database it resides in.
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What is the difference between precision and scale?
...on. e.g: Precision 4, scale 2 - will fail any number > 99.9999..; try: select cast (99.99999 as NUMBER(4,2)) from dual; //OK; select cast (100.9 as NUMBER(4,2)) from dual; //FAIL;
– Jama Djafarov
Mar 6 '15 at 17:47
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SQL Group By with an Order By
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In all versions of MySQL, simply alias the aggregate in the SELECT list, and order by the alias:
SELECT COUNT(id) AS theCount, `Tag` from `images-tags`
GROUP BY `Tag`
ORDER BY theCount DESC
LIMIT 20
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Can you animate a height change on a UITableViewCell when selected?
... I would like it so that when the user clicks on a particular person (thus selecting the cell), the cell grows in height to display several UI controls for editing the properties of that person.
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