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Why does overflow:hidden not work in a ?
I've got a table cell that I would always like to be a particular width. However, it doesn't work with large strings of unspaced text. Here's a test case:
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How many database indexes is too many?
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It depends on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow w...
What are the differences between virtual memory and physical memory?
...perating system creates and deals with these mappings - utilizing the page table, among other data structures to maintain the mappings. Virtual memory mappings are always found in the page table or some similar data structure (in case of other implementations of virtual memory, we maybe shouldn't ca...
Delete duplicate rows from small table
I have a table in a PostgreSQL 8.3.8 database, which has no keys/constraints on it, and has multiple rows with exactly the same values.
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A dependent property in a ReferentialConstraint is mapped to a store-generated column
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Is it possible that you defined a bad column relation between your tables? different columns and one was set as autonumeric.
It happened to me.
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SET versus SELECT when assigning variables?
... @var varchar(20)
set @var = 'Joe'
set @var = (select name from master.sys.tables where name = 'qwerty')
select @var /* @var is now NULL */
set @var = 'Joe'
select @var = name from master.sys.tables where name = 'qwerty'
select @var /* @var is still equal to 'Joe' */
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Facebook database design?
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Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
Emai...
Django ManyToMany filter()
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another way to do this is by going through the intermediate table. I'd express this within the Django ORM like this:
UserZone = User.zones.through
# for a single zone
users_in_zone = User.objects.filter(
id__in=UserZone.objects.filter(zone=zone1).values('user'))
# for multiple zo...
Is there a combination of “LIKE” and “IN” in SQL?
...an use REGEXP_LIKE (available from Oracle version 10 onwards).
An example table:
SQL> create table mytable (something)
2 as
3 select 'blabla' from dual union all
4 select 'notbla' from dual union all
5 select 'ofooof' from dual union all
6 select 'ofofof' from dual union all
7 ...
SELECT * FROM X WHERE id IN (…) with Dapper ORM
...er supports this directly. For example...
string sql = "SELECT * FROM SomeTable WHERE id IN @ids"
var results = conn.Query(sql, new { ids = new[] { 1, 2, 3, 4, 5 }});
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