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Big-O summary for Java Collections Framework implementations? [closed]
...s next notes
HashSet O(1) O(1) O(h/n) h is the table capacity
LinkedHashSet O(1) O(1) O(1)
CopyOnWriteArraySet O(n) O(n) O(1)
EnumSet O(1) O(1) O(1)
TreeSet O(log n) O(log n) O(log n)
ConcurrentSkipListSet O...
“static const” vs “#define” vs “enum”
...s pointers around.
Both (1) and (3) have a symbol in the debugger's symbol table - that makes debugging easier. It is more likely that (2) will not have a symbol, leaving you wondering what it is.
(1) cannot be used as a dimension for arrays at global scope; both (2) and (3) can.
(1) cannot be used...
How to delete the top 1000 rows from a table using Sql Server 2008?
I have a table in SQL Server. I would like to delete the top 1000 rows from it. However, I tried this, but I instead of just deleting the top 1000 rows it deleted all the rows in the table.
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Length of a JavaScript object
... implemented method, but you can check which browser supports it with this table.
– aeosynth
Jun 6 '11 at 19:08
51
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The conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value
...n using Entity Framework. This occurs when the entity associated with the table being saved has a mandatory datetime field and you do not set it with some value.
The default datetime object is created with a value of 01/01/1000 and will be used in place of null. This will be sent to the datetime ...
Easiest way to rename a model using Django/South?
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To answer your first question, the simple model/table rename is pretty straightforward. Run the command:
./manage.py schemamigration yourapp rename_foo_to_bar --empty
(Update 2: try --auto instead of --empty to avoid the warning below. Thanks to @KFB for the tip.)
If ...
How does collections.defaultdict work?
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Neither. 0 is immutable - in CPython all values from -5 to 256 are cached singletons but this is implementation-specific behaviour - in both cases a new instance is "created" each time with int() or list(). That way, d[k].append(v) can work wi...
Rails: Using greater than/less than with a where statement
...non discrete values or columns where you can't use the + 1 strategy.
Arel table
If you want to get fancy you can make use of the Arel::Table.
User.where(User.arel_table[:id].gt(200))
will generate the SQL
"SELECT `users`.* FROM `users` WHERE (`users`.`id` > 200)"
The specifics are as foll...
Order a MySQL table by two columns
How do I sort a MySQL table by two columns?
5 Answers
5
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How do you list all triggers in a MySQL database?
...ll triggers is:
show triggers;
or you can access the INFORMATION_SCHEMA table directly by:
select trigger_schema, trigger_name, action_statement
from information_schema.triggers
You can do this from version 5.0.10 onwards.
More information about the TRIGGERS table is here.
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