The Machinery Information Management Open Systems Alliance have developed an information schema which developers of machinery information software can relate their machinery data stored in a proprietary database or file specification. The most widely-used method of specifying an information schema is a relational method. Vendor independence is vital to the success of the project. Many vendors or users have implemented various relational databases and modeled machinery data in various ways.
Updates can flow from one database to another without going through a centralized database.
In order to maintain database consistency in this architecture, the date of the last update on every row of data, along with the status of the row is maintained. A local reference timestamp is also supported on measurements to display the local time a measurement was recorded for an operator. The relational schema allows for each database, however, to create and maintain additional reference table entries to allow the maximum flexibility. The tables which must be supported for the given technology, data category, and version are listed in this matrix. There are two types of SQL support.