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What is a good reason to use SQL views?
...one extra column active.
If your system(s) have gazillion queries that do SELECT whatever FROM T_OLD WHERE whatever, you have two choices for the roll-out:
1) Cold Turkey - Change the DB, and at the same time, change, test and release numerous pieces of code which contained said query. VERY hard t...
Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
Haskell offline documentation?
...ossibilities, if any, for getting offline docs for Haskell core libraries (and maybe more)?
9 Answers
...
How to get rid of Git submodules untracked status?
...ay to have a clean status would be to go into each one of those submodules and:
add and commit the untracked contents,
or reference the untracked contents in a .gitignore specific to each module.
or you can add the same ignored content to the submodule's .git/info/exclude, as peci1 reports in th...
How do I update Ruby Gems from behind a Proxy (ISA-NTLM)
...
I wasn't able to get mine working from the command-line switch but I have been able to do it just by setting my HTTP_PROXY environment variable. (Note that case seems to be important). I have a batch file that has a line like this in it:
SET HTTP_PROXY=http://%USER%:%PAS...
MySQL get the date n days ago as a timestamp
...
DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
1244433347
...
JPA : How to convert a native query result set to POJO class collection
...e done with an entity.
For instance:
Query query = em.createNativeQuery("SELECT name,age FROM jedi_table", Jedi.class);
@SuppressWarnings("unchecked")
List<Jedi> items = (List<Jedi>) query.getResultList();
But in this case, Jedi, must be a mapped entity class.
An alternative to avoi...
Throwing the fattest people off of an overloaded airplane.
...uch better. I use something quite like this for a recommendation engine (I select the top 200 items from a list of several million). I typically end up with only 50,000 or 70,000 items actually added to the heap.
I suspect that you'll see something quite similar: the majority of your candidates wil...
MySQL: Transactions vs Locking Tables
...ransactions vs locking tables to ensure database integrity and make sure a SELECT and UPDATE remain in sync and no other connection interferes with it. I need to:
...
Cause of a process being a deadlock victim
I have a process with a Select which takes a long time to finish, on the order of 5 to 10 minutes. I am currently not using NOLOCK as a hint to the MS SQL database engine. At the same time we have another process doing updates and inserts into the same database and same tables. The first pr...