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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...
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...
Checkbox for nullable boolean
...ents your null, whatever the semantics of null means. You could use a <select><option> drop down list to save real estate, but the user has to click twice and the choices aren't nearly as instantaneously clear.
1 0 null
True False Not Set
Yes No Undecided
Male Fema...
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...
How to convert the ^M linebreak to 'normal' linebreak in a file opened in vim?
... Solution's response didn't work for me, only @MateenUlhaq commands helped me.
– Edenshaw
Jul 26 '18 at 17:05
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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...
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:
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pip install mysql-python fails with EnvironmentError: mysql_config not found
...3.17-0/mysql/bin If you're using this commercial MAMP stack, on the other hand, uninstall it and get the bitnami one because it is shit and doesn't include the mysql headers.
– Timmmm
Oct 8 '12 at 11:20
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Specifying rails version to use when creating a new application
I have two versions of rails (2.1.0 and 2.2.2) installed in my computer.
7 Answers
7
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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...