Index SAP Sybase IQ Columns

SAP Sybase IQ indexes are designed to make the best use of memory, disk and CPU cycles for specific types of queries.

Index sizes usually remain small. The entire database can be fully indexed and made available for ad hoc queries in the same space that would be needed to store the raw data. Traditional databases often need three or more times more space.
Queries are resolved by efficiently combining and manipulating indexes on only the relevant columns. This avoids time-consuming table scans.
I/O is minimized, eliminating potential bottlenecks.
Because indexes are compact, more data can be kept in memory for subsequent queries, thereby speeding throughput on iterative analysis.
Tuning is data dependent, allowing data to be optimized once for any number of ad hoc queries.

Overview of Indexes
Indexes improve data retrieval performance. SAP Sybase IQ indexes differ from traditional indexes and are designed to accelerate queries in the data warehousing environment.
Index Types Comparison
Choose the column index type appropriate to your task.
Criteria for Choosing Indexes
The set of indexes that you define for any given column can have dramatic impact on the speed of query processing.
Creating Indexes
SAP Sybase IQ automatically creates a default index on every table column when you create a database in an IQ store. For best query performance, create additional indexes.
Running the Index Advisor
If you set the INDEX_ADVISOR option on your database, SAP Sybase IQ issues messages in the message log or query plan to suggest additional indexes that might improve performance.
Renaming Indexes
You can rename an index in a base table or global temporary table with the owner type USER.
Viewing Indexes
Use the stored procedure sp_iqindex to see information about indexes.
Removing Indexes
Remove column indexes that are no longer required.
Retaining Indexes When Removing Foreign Key Constraints
You may want to remove a foreign key constraint, but retain the underlying HG index. A non-unique HG index can provide query performance improvement, but may be expensive to build.
Optimizing Performance for Joins
You can create indexes to optimize join performance.