Summarizing statistical data for database systems and/or environments

Abstract

Database values and their associated indicators can be arranged in multiple “buckets.” Adjacent buckets can be combined into a single bucket successively based one or more criteria associated with the indicators to effectively reduce the number of buckets until a desired number is reached.

1 . A method of storing database values and their associated indicator values in a summarized form in a database that stores data, wherein the method is implemented at least partly by a device, and wherein the method comprises:
 arranging multiple buckets that include multiple database values of a database in accordance with an order in an arrangement based on the database values, wherein each one of the database values is associated with an indicator value, and wherein each one of the multiple buckets includes only one of the database values with its associated indicator value;   determining whether to reduce the number of buckets arranged in the arrangement;   combining two adjacent buckets in the arrangement into a combined bucket at least partly based the difference between the indicator values if the two adjacent buckets when the determining determines to reduce the number of buckets; and   repeating the determining of whether to reduce the number of buckets and the combining of yet another two adjacent buckets in the arrangement into another combined bucket until the determining determines not to further reduce the number of buckets.   
     
     
         2 . The method of  claim 1 ,
 wherein the database values are column values of a database table of a database, and wherein their associated indicator values are their frequency of occurrence in the database table;   wherein determining whether to reduce the number of buckets arranged in the arrangement includes determining whether two frequencies of occurrence of two adjacent buckets are within an acceptable range of difference, and   wherein the determining of whether reduce the number of buckets includes determining whether a desired total number of buckets has been reached, and wherein the repeating repeats the combining for yet another two adjacent buckets until the determining determines not to further reduce the number of buckets as the desired total number of buckets has been reached.   
     
     
         3 . The method of  claim 1 , wherein the one or more criteria include an error criterion determined based on the difference between two or more of the indicator values. 
     
     
         4 . The method of  claim 1 , wherein the desired total number of buckets is provided as input. 
     
     
         5 . The method of  claim 1 , wherein the one or more criteria include the desirability for not combining one or more of the database values with one or more other database values of the database values. 
     
     
         6 . The method of  claim 5 , wherein the method further comprises: adding an additional error value to a default error value associated with the one or more database values that are not desired to be combined with the one or more other database values of the database values, thereby reducing the likelihood of combining that the one or more database values with the one or more other database values. 
     
     
         7 . The method of  claim 5 , wherein the method further comprises: integrating a workload constraint into a combining strategy for combining the buckets; and adding a preliminary constant error value to a default delta-error associated with the one or more database values in an attempt to avoid combining the one or more database values with the one more other database values. 
     
     
         8 . The method of  claim 2 , wherein the method further comprises: determining the desired total number of buckets by considering one or more of the following: cost of memory, storage, computational resources for maintaining a histogram, and input provided by a database administrator and/or database user. 
     
     
         9 . The method of  claim 1 , wherein the method further comprises: receiving as input through a user interface the desired total number of buckets and the one or more criteria. 
     
     
         10 . An apparatus that includes one or more processors operable to store database values and their associated indicator values in a summarized form, by performing at least the following:
 arranging multiple buckets that include multiple database values of a database in accordance with an order in an arrangement based on the database values, wherein each one of the database values is associated with an indicator value, and wherein each one of the multiple buckets includes only one of the database values with its associated indicator value;   determining whether to reduce the number of buckets arranged in the arrangement;   combining two adjacent buckets in the arrangement into a combined bucket at least partly based the difference between the indicator values if the two adjacent buckets when the determining determines to reduce the number of buckets; and   repeating the determining of whether to reduce the number of buckets and the combining of yet another two adjacent buckets in the arrangement into another combined bucket until the determining determines not to further reduce the number of buckets.   
     
     
         11 . The apparatus of  claim 10 , wherein the determining of whether reduce the number of buckets determines whether a desired total number of buckets has been reached, and wherein the repeating repeats the combining for yet another two adjacent buckets until the determining determines not to further reduce the number of buckets as the desired total number of buckets has been reached. 
     
     
         12 . The apparatus of  claim 10 , wherein the one or more criteria include an error criterion determined based on the difference between two or more of the indicator values. 
     
     
         13 . The apparatus of  claim 10 , wherein the desired total number of buckets is provided as input. 
     
     
         14 . The apparatus of  claim 10 , wherein the one or more criteria includes the desirability for not combining one or more of the database values with one or more other database values of the database values. 
     
     
         15 . The apparatus of  claim 10 , wherein the storing of the database values and their associated indicator values in a summarized form further comprises: integrating a workload constraint into a combining strategy for combining the buckets; and adding a preliminary constant error value to a default delta-error associated with the one or more database values in an attempt to avoid combining the one or more database values with the one more other database values. 
     
     
         16 . A non-transitory computer readable storage medium storing at least computer code that when execute stores database values and their associated indicator values in a summarized form by at least:
 arranging multiple buckets that include multiple database values of a database in accordance with an order in an arrangement based on the database values, wherein each one of the database values is associated with an indicator value, and wherein each one of the multiple buckets includes only one of the database values with its associated indicator value;   determining whether to reduce the number of buckets arranged in the arrangement;   combining two adjacent buckets in the arrangement into a combined bucket at least partly based the difference between the indicator values if the two adjacent buckets when the determining determines to reduce the number of buckets; and   repeating the determining of whether to reduce the number of buckets and the combining of yet another two adjacent buckets in the arrangement into another combined bucket until the determining determines not to further reduce the number of buckets.   
     
     
         17 . The non-transitory computer readable storage medium of  claim 16 , wherein the determining of whether reduce the number of buckets determines whether a desired total number of buckets has been reached, and wherein the repeating repeats the combining for yet another two adjacent buckets until the determining determines not to further reduce the number of buckets as the desired total number of buckets has been reached. 
     
     
         18 . The non-transitory computer readable storage medium of  claim 16 , wherein the one or more criteria include an error criterion determined based on the difference between two or more of the indicator values. 
     
     
         19 . The non-transitory computer readable storage medium of  claim 16 , wherein the desired total number of buckets is provided as input. 
     
     
         20 . The non-transitory computer readable storage medium of  claim 16 , wherein the one or more criteria includes the desirability for not combining one or more of the database values with one or more other database values of the database values.