XML indexes can be created on XML data type columns. It indexes all tags, values, and paths over the XML instances in the column and can result in improved query performance. XML indexing can be very useful in the following scenarios. |
When there is a need to frequently execute queries on XML columns. |
When the values you retrieve from XML values are relatively small compared to the size of the |
XML column itself. By indexing that XML column, you can avoid parsing the whole data at run- time and be benefited by index lookups for efficient query processing. |
There are two types of indexes that can be created on an XML column. They are primary XML index and secondary XML index. As the name suggests, the first index on an XML column is the primary XML index. Using it, three types of secondary XML indexes can be created on the XML column to speed up |
common classes of queries.
learn guitarphysics learnteliphonyxmlphysicsenjoylife