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How can I make a JPA OneToOne relation lazy
...relations were lazy so that wasn't the problem. When inspecting the actual SQL being executed, I noticed that there were over 80 joins in the query.
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How does comparison operator works with null int?
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Comparing C# with SQL
C#: a=null and b=null => a==b => true
SQL: a=null and b=null => a==b => false
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How to add multiple objects to ManyToMany relationship at once in Django ?
...sdolan is in fact (currently) incorrect. I.e. when I look at the generated SQL I see only a single insert statement: INSERT INTO app_one_twos (one_id, two_id) VALUES (1, 1), (1, 2), (1, 3), (1, 4); This is in Django 1.4.
– Klaas van Schelven
Mar 26 '13 at 16...
Create an index on a huge MySQL production table without table locking
I need to create an index on a ~5M rows MySQL table. It is a production table, and I fear a complete block of everything if I run a CREATE INDEX statement...
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Difference between Document-based and Key/Value-based databases?
I know there are three different, popular types of non-sql databases.
2 Answers
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Best way to use PHP to encrypt and decrypt passwords? [duplicate]
...me way your application can. You could still get some protection from some SQL injection attacks and misplaced db backups if you store a secret key in a file and use that to encrypt on the way to the db and decrypt on the way out. But you should use bindparams to completely avoid the issue of SQL in...
Linq: GroupBy, Sum and Count
...ame is always the same for any given code, but apparently generates better SQL in EF.
I'd also suggest that you should change the Quantity and Price properties to be int and decimal types respectively - why use a string property for data which is clearly not textual?
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How to use LINQ to select object with minimum or maximum property value
...be slower than the other solution suggested. However, if this is a LINQ to SQL table and DateOfBirth is an indexed column, then SQL Server will use the index instead of sorting all the rows. Other custom IEnumerable<T> implementations could also make use of indexes (see i4o: Indexed LINQ, or t...
Count work days between two dates
How can I calculate the number of work days between two dates in SQL Server?
23 Answers
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Django - limiting query results
...with no database access.
As you can see below your code only executes one sql query to fetch only the last 10 items.
In [19]: import logging
In [20]: l = logging.getLogger('django.db.backends')
In [21]: l.setLevel(logging.DEBUG)
In [22]: l...