With the goal of developing a benchmark for Schema Evolution, this page provides some detailed information on various schema evolution tools used to compile different versions that a dataset has undergone and the analysis of these schemas to generate the SQL statements leading to those evolutions. Also includes the set of corresponding SMOs and ICMOs used by PRISM for automatic query generation for the datasets at hand.
" Change is the law of nature ". Confirming to this law of nature, Information systems are highly subjected to continuous change. This change could be a change in data, schema, applications or queries. Open source s/w development has also added to the magnitude of changes or evolution. Evolution adds complexity and the impact of any evolution could be very strong on Information Systems. If we talk about Schema Evolution, it is still in its younger days. Tools such as PRISM, PRIMA, HMM (Curino et al. 2008) have been recently proposed to assist in graceful schema evolution. The DB group at UCLA is in a process of setting up a benchmark for such tools. As part of the effort this page contains useful information, useful links to some tools and histories of datasets that have been used to test the efficiency of those tools.Three datasets namely wikipedia, ensembl, xoops have been analyzed to extract Schema Modification Operators(SMOs) and Integrity Constraints Modification Operators (ICMOs).
The Schema Evolution Toolsuite (SET), a tool developed by Fabrizio Moroni, is a framework to easily automate the benchmarking process. It collects statistical information on schema evolution of a dataset.The data about the evolution of a schema is stored in the form of meta-data i.e. Information Schema is used to store this data in a MYSQL database.
The SQL2SMO translator tool is developed by Fabrizio Moroni and it translates the given patch of SQL statements into corresponding Schema Modification Operators(SMOs) using some pattern matching techniques. It identifies five types of patterns viz. Join Pattern Type1, Join Pattern Type2, Merge Pattern, Partition Pattern, and Decompose Pattern.