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How to get object size in memory? [duplicate]
...would know, Int32 and float are four
bytes, double and DateTime 8 bytes, char is actually two bytes (not
one byte), and so on. String is a bit more complex, 2*(n+1), where n
is the length of the string. For objects, it will depend on their
members: just sum up the memory requirement of all i...
What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
...ent attribute. Otherwise, (valid at least for PG) you might get ERROR: for SELECT DISTINCT, ORDER BY expressions must appear in select list
– long
Apr 21 at 14:08
add a commen...
Cannot simply use PostgreSQL table name (“relation does not exist”)
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In other words, the following fails:
CREATE TABLE "SF_Bands" ( ... );
SELECT * FROM sf_bands; -- ERROR!
Use double-quotes to delimit identifiers so you can use the specific mixed-case spelling as the table is defined.
SELECT * FROM "SF_Bands";
Re your comment, you can add a schema to th...
Find closing HTML tag in Sublime Text
...trl+Shift+A for Windows and Linux users, Command+Shift+A for Mac users) to select the whole block within the currently selected tag.
For example, if you pressed this while your text cursor was within the outer div tag in the code below, all the divs with class selected would be selected.
<div c...
How to get value of selected radio button?
I want to get the selected value from a group of radio buttons.
28 Answers
28
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How to get the first and last date of the current year?
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SELECT
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()), 0) AS StartOfYear,
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()) + 1, -1) AS EndOfYear
The above query gives a datetime value for midnight at the beginning of December 31. This ...
Postgres manually alter sequence
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The parentheses are misplaced:
SELECT setval('payments_id_seq', 21, true); # next value will be 22
Otherwise you're calling setval with a single argument, while it requires two or three.
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Remove the last character in a string in T-SQL?
... ELSE LEFT(@String, LEN(@String) - 1)
END
) END
SELECT @String
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Glorified classes in the Java language
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@aioobe: exactly. Note that you also have int.class, char.class, etc.
– Michael Borgwardt
Aug 11 '10 at 13:19
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Count Rows in Doctrine QueryBuilder
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Something like:
$qb = $entityManager->createQueryBuilder();
$qb->select('count(account.id)');
$qb->from('ZaysoCoreBundle:Account','account');
$count = $qb->getQuery()->getSingleScalarResult();
Some folks feel that expressions are somehow better than just using straight DQL. One...