Dynamic partial uncompression of a database table

摘要

A database dynamic partial uncompression mechanism determines when to dynamically uncompress one or more compressed portions of a database table that also includes uncompressed portions. A query may include an express term that specifies whether or not to skip compressed portions. In addition, a query may include associated information that specifies whether or not to skip compressed portions, and one or more thresholds that may be used to determine if the system is too busy to perform uncompression. A display mechanism may also determine whether or not to display compressed portions. The uncompression may occur at the database server or at a client. The database dynamic partial uncompression mechanism thus performs dynamic uncompression in a way that preferably uncompresses one or more compressed portions of a partially compressed database table only when the compressed portions satisfy a query and/or need to be displayed.

主权项

1. An apparatus comprising:
at least one processor; a memory coupled to the at least one processor; a database table residing in the memory that includes at least one portion that is compressed and at least one portion that is uncompressed; an uncompression mechanism residing in the memory and executed by the at least one processor that determines a first portion of the database table is a first compressed portion that satisfies the query, determines whether the query includes a parameter that specifies to skip compressed portions, and in response to determining the query includes the parameter that specifies to skip compressed portions, displaying a first result set for the query that does not include the first compressed portion, and in response to determining the query does not include the parameter that specifies to skip compressed portions, uncompressing the first compressed portion and displaying a second result set for the query that includes the uncompressed first portion; and a display mechanism residing in the memory and executed by the at least one processor, the display mechanism displaying a result set that includes compressed data and determining when and how to display the compressed data in the result set.