Newbie question about indexes

Newbie question about indexes

• MatrixObjects

  Here's what the optimizer guys have to say:
  
  

  One index should be fine if he always has every column in the WHERE condition and he is doing equality matching.< xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

  This will give two main plan options:

  1. index lookup + fetch
  2. table scan

  It will be a cost-based decision.

  
  
  

• Brick IM Robot

  Hi,
  
  I expect to return c. 100 rows. (Would indexing strategy differs if I have return whole table )
  Retrieval speed is priority.
  I have no other queries for this table.
  
  Thank you

  
  
  

• SteveNash72

  Strictly from your query perspective, you will only need one index with the key (col1...colN). However, this index will be useless if say col1 is missing from your where clause. So  you need to evaluate full set of queries that you plan to run on this table. Also, as Eric points out, you will need to evaluate the cost of updating indexes if you have lots of updates/inserts/deletes
  Thanks
  
  

• Toby Sharp

  How many rows do you expect it to return
  Do you prefer retrieval speed over update speed
  Do you have other queries that might benefit from individual indexes
  

  
  
  
• Newbie question about indexes