Method of reusing existing statistics to load database tables

Abstract

An indication to load data into a database table is received. A determination is made whether an existing set of frequency distribution statistics is available. In response to determining that an existing set of frequency distribution statistics is available, the data is loaded into the database table using the existing set of frequency distribution statistics.

What is claimed is: 
     
         1 . A method for using existing frequency distribution statistics to load data into database tables, the method comprising:
 receiving, by one or more computer processors, an indication to load data into a database table included in a database management system, wherein the data consists of a first portion of data and a second portion of data;   determining, by one or more computer processors, whether an existing set of frequency distribution statistics is available for the data, wherein the existing set of frequency distribution statistics are generated independently of the database management system prior to loading the data into the database management system, wherein the set of frequency distribution statistics for the data is used to create a compression dictionary the data for use by a database management system, wherein the compression dictionary is a simple lookup table which uses fewer bits to store data when compared to the data itself, and wherein the compression dictionary is used to load the data into the database table;   responsive to determining that an existing set of frequency distribution statistics for the data is available, loading, by one or more computer processors, the data into the database table using the existing set of frequency distribution statistics for the data;   responsive to determining that an existing set of frequency distribution statistics is not available for the first portion of data but an existing set of frequency distribution statistics is available for the second portion of data, generating, by one or more computer processors, a set of frequency distribution statistics for the first portion of data that does not have the existing set of frequency distribution statistics available;   responsive to generating a set of frequency distribution statistics for the first portion of data that does not have the existing set of frequency distribution statistics available, loading, by one or more computer processors, the data into the database table using the generated set of frequency distribution statistics for the first portion of data that does not have the existing set of frequency distribution statistics available and the existing set of frequency distribution statistics for the second portion of data that does have the existing set of frequency distribution statistics available;   responsive to determining that an existing set of frequency distribution statistics for the data is not available, generating, by one or more computer processors, a set of frequency distribution statistics for the data; and   responsive to generating the set of frequency distribution statistics for the data, loading, by one or more computer processors, the data into the database table using the generated set of frequency distribution statistics for the data.