PREDICATE APPLICATION THROUGH PARTIAL COMPRESSION DICTIONARY MATCH
First Claim
1. A computer-implemented method for predicate application using partial compression dictionary match, the method comprising:
- developing a search strategy for each predicate to be applied to compressed data, the search strategy comprising;
searching entries of a compression dictionary for an entire predicate value to identify each matching symbol and noting an exact match, and a subsumed match of a compression symbol in a search list;
searching the entries of the compression dictionary to identify entries in which a predicate prefix forms a dictionary entry suffix and noting each matching compression symbol in the search list;
searching the entries of the compression dictionary to identify entries in which a predicate suffix forms a dictionary entry prefix and noting each matching compression symbol in the search list;
searching the entries of the compression dictionary to identify entries which form a mid-predicate match and noting each matching compression symbol in the search list; and
adding one or more uncompressed symbol for predicates having no match in the compression dictionary, and for predicates having only one or more subsumed dictionary matches;
searching the compressed data to locate the compression symbols identified in the search list; and
in response to locating a compression symbol from the search list in the compressed data,decompressing a respective row and applying the predicate;
returning a respective row that matches the predicate to one of;
a database engine and an application.
1 Assignment
0 Petitions
Accused Products
Abstract
Apparatus and systems, including computer program products, implementing and using techniques for predicate application using partial compression dictionary match. A search strategy is developed for each predicate to be applied to compressed data. The compressed data is searched using the search strategy to locate the compression symbols identified in the search strategy. In response to locating a compression symbol from the search strategy in the compressed data, a respective row and applying the predicate is decompressed and a respective row that matches the predicate is returned to a database engine or an application.
-
Citations
9 Claims
-
1. A computer-implemented method for predicate application using partial compression dictionary match, the method comprising:
-
developing a search strategy for each predicate to be applied to compressed data, the search strategy comprising; searching entries of a compression dictionary for an entire predicate value to identify each matching symbol and noting an exact match, and a subsumed match of a compression symbol in a search list; searching the entries of the compression dictionary to identify entries in which a predicate prefix forms a dictionary entry suffix and noting each matching compression symbol in the search list; searching the entries of the compression dictionary to identify entries in which a predicate suffix forms a dictionary entry prefix and noting each matching compression symbol in the search list; searching the entries of the compression dictionary to identify entries which form a mid-predicate match and noting each matching compression symbol in the search list; and adding one or more uncompressed symbol for predicates having no match in the compression dictionary, and for predicates having only one or more subsumed dictionary matches; searching the compressed data to locate the compression symbols identified in the search list; and in response to locating a compression symbol from the search list in the compressed data, decompressing a respective row and applying the predicate; returning a respective row that matches the predicate to one of;
a database engine and an application. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
Specification