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Postgresql - change the size of a varchar column to lower length
... really large table (almost 30 millions rows).
One of its columns is a varchar(255) and I would like to resize it to a varchar(40) .
Basically, I would like to change my column by running the following command:
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How do you do a limit query in JPQL or HQL?
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// SQL: SELECT * FROM table LIMIT start, maxRows;
Query q = session.createQuery("FROM table");
q.setFirstResult(start);
q.setMaxResults(maxRows);
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Bootstrap 3: Keep selected tab on page refresh
I am trying to keep selected tab active on refresh with Bootstrap 3 . Tried and checked with some question already been asked here but none of work for me. Don't know where I am wrong. Here is my code
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Best approach to remove time part of datetime in SQL Server
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Strictly, method a is the least resource intensive:
a) select DATEADD(dd, DATEDIFF(dd, 0, getdate()), 0)
Proven less CPU intensive for same total duration a million rows by some one with way too much time on their hands: Most efficient way in SQL Server to get date from date+ti...
Best way to create unique token in Rails?
...ittle bit of code in his Railscast on beta invitations. This produces a 40 character alphanumeric string.
Digest::SHA1.hexdigest([Time.now, rand].join)
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Escape Character in SQL Server
...s the second answer shows it's possible to escape single quote like this:
select 'it''s escaped'
result will be
it's escaped
If you're concatenating SQL into a VARCHAR to execute (i.e. dynamic SQL), then I'd recommend parameterising the SQL. This has the benefit of helping guard against SQL in...
Unbound classpath container in Eclipse
... or 4. goto Properties -> Java Build Path -> Libraries Tab -> Select the erroneous system library -> Edit (On the right) -> Select alternate JRE -> Finish.
– Rajkiran
Jun 26 '14 at 12:11
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Return a `struct` from a function in C
... Yes, I can put an array inside a struct, but I cannot e.g. write typedef char arr[100]; arr foo() { ... } An array cannot be returned, even if the size is known.
– Giorgio
Mar 11 '12 at 11:19
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SQL Server - Create a copy of a database table and place it in the same database?
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Use SELECT ... INTO:
SELECT *
INTO ABC_1
FROM ABC;
This will create a new table ABC_1 that has the same column structure as ABC and contains the same data. Constraints (e.g. keys, default values), however, are -not- copied.
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Drop data frame columns by name
...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it.
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