I access several tables remotely via DB Link. They are very normalized and the data in each is effective-dated. Of the millions of records in each table, only a subset of ~50k are current records. The tables are internally managed by a commercial product that will throw a huge fit if I add indexes or make alterations to its tables in ...
Which type of index(clustered/non clustrered) should be used for Insert/Update/Delete statement in SQL Server. I know it creates an additional overhead but is it better in performance as comparison to non clustered index? Also which index should be use for Select statements in SQL Server? ...
I need to store a undirected graph in a Google App Engine database. For optimization purposes, I am thinking to use database indexes. Using Google App Engine, is there any way to define the columns of a database table to create its index? I will need some optimization, since my app uses this stored undirected graph on a content-based fi...
I'm working in Sql Server 2005. I have an event log table that tracks user actions, and I want to make sure that inserts into the table are as fast as possible. Currently the table doesn't have any indexes. Does adding a single non-clustered index slow down inserts at all? Or is it only clustered indexes that slow down inserts? Or should...
Content of a website is stored in a MySQL database. 99% of the content will be enabled, but some (users, posts etc.) will be disabled. Most of the queries end as WHERE (...) AND enabled Is it a good idea to create an index on the field 'enabled'? ...
Where can I find information on whether which databases are using B+Trees over B-Trees for their index implementations? Oracle appears to be using B+Trees. Although they don't describe it on their documentation, their graphics appear to be pointing that B+Trees are actually being used. ...
I have annotation-driven hibernate capabilies on my project. Now I want to create an index over a column. My current column definition is @NotNull @Column(name = "hash") private String hash; and I add @Index annotation here. @NotNull @Column(name = "hash") @Index(name="hashIndex") private String hash; and then DROP TABLE and resta...
I am trying to generate hibernate-mapping from POJOs with hibernate annotations. Then I want to use liquibase to generate database schema. So I need indexes to be defined in my POJOs. Sample POJO: @Entity public class A { @Id @GeneratedValue private Long id; @Index(name = "IDX_NAME") @ForeignKey(name="sd") p...
form wikipedia:http://en.wikipedia.org/wiki/Index_(database) Some databases extend the power of indexing by allowing indexes to be created on functions or expressions. For example, an index could be created on upper(last_name), which would only store the upper case versions of the last_name field in the index. Another option sometime...
Sorry all, I do have this mini table with 3 columns but, I will list the values either by one or other column. 1) Is it ok to have two of those columns with indexes? 2) Should we have only one index per table? 3) At the limit, if we have a table with 100 columns for example, and we have 50 of them with indexes, is this ok? Thanks...
Is there going to be any real benefit to me putting indexes onto date fields that are going to be mainly used in queries using stuff like. dateField < 'var' And 'var' BETWEEN dateField1 AND dateField2 The searches get done a lot but I am never doing a direct comparison "=" on them. ...