Rejecting rows when scanning a collision chain that is associated with a page filter

摘要

Provided are techniques for locating a row. A page filter in a page is stored, wherein the page filter is associated with a collision chain and includes a portion of a hash value of the row in the collision chain that has overflowed to an overflow area. In response to a request to locate a target row, the page filter is used to determine that the row has overflowed based on a portion of a hash value of the target row matching the portion of the hash value of the row that has overflowed.

主权项

1. A method, comprising:
storing, using a processor of a computer, a page filter in a page, wherein the page filter is associated with a collision chain and includes a portion of a hash value of a row in the collision chain that has overflowed to an overflow area; dynamically adjusting the page filter to store different portions of the hash value for the overflowed row as a number of overflowed rows increases; and in response to a request to locate a target row, using the page filter to determine that the row has overflowed based on a portion of a hash value of the target row matching the portion of the hash value of the row that has overflowed.