CONSTRAINT SATISFACTION SOFTWARE TOOL FOR DATABASE TABLES

摘要

Techniques and solutions are provided for analyzing constraints. A disclosed embodiment provides for determining whether a table contains a valid tuple, and if so, the minimum index of the first valid tuple. Determining whether the table contains a valid tuple can provide an early indication of whether a set of constraints is violated or entailed, for positive and negative constraints, respectively. Determining the minimum index of the first valid tuple can expedite subsequent constraint analysis. Further disclosed embodiments provide for removal of duplicate and wildcard values from a set of constraints, which can facilitate negative constraint analysis. An indication can be provided, such as through a user interface, of whether a set of constraints is violated or entailed. Software can restrict selection of values that may result in constraint violation based on the provided indication.