| 摘要 |
An update to a primary table is received. The primary table is read to determine the set of rows to be updated. The primary table is updated and XML objects stored in XML columns are overwritten according to the update. A pre-update node table comprising the nodes corresponding to the updated rows is created from an XML index table corresponding to the primary table. A post-update node table is created by shredding the updated XML objects. The post-update table and the pre-update table are merged according to their node identifiers. The resulting merged table can be inspected to determine which nodes have been, added, deleted, or updated. Based on this inspection, the necessary additions and deletions can be efficiently made to the XML index table.
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