I have a self referencing table in Oracle 9i, and a view that gets data from it: CREATE OR REPLACE VIEW config AS
开发者_开发知识库alt text http://img502.imageshack.us/img502/7245/75088152.jpg There are two tables that I join them together, one of them is a temp table and I create an index after creating the tab
I made a Dictionary<string, string> collection so that I can quickly reference the items by their string identifier.
If I have a table column with data and create an index on this column, will the index take same amount of disc space as the column itself?
I need to optimize a MYSQL query doing an order by. No matter what I do, mysql en开发者_开发问答ds up doing a filesort instead of using the index.
In Numpy, ix_() is used to grab rows and columns of a matrix, but it doesn\'t seem to work with sparse matrices. For instance, this code works because it uses a dense matrix:
Hi I have a MySQL table, let\'s say it is a helpdesk ticketing system. It has a CLOSED column, which I want to index. 99% of time, I will need to only select on OPEN tickets, so something like
hi i\'m doing a program that needs high performance of handling vector elements vector<Class_A> object ;
Looking through a few SQL implementations, I noticed that most DBMSs support defining an index on a column with a descinding order, e.g.
I have a two column table with a primary key (int) and a unique value (nvarchar(255)) When I insert a value to this table, I can use Scope_identity() to return the primary key for the value I just in
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