Embedded Mobile Real-time Database Management System Data Dictionary's Structure And Management

Embedded mobile real-time database management system(EMRTDBMS) is a sort of database management system which is embedded in all kinds of equipment, specially mobile equipment, and supports mobile computation. Data dictionary is an important constituent of data management. EMRTDBMS needs to support mobile computation environment, and realize the time limit of transaction. It must expand the traditional data dictionary accordingly.Data dictionary increases fixed network table, network node table, data distribution table, MSS table, mobile client table, mobile client access jurisdiction table, mobile client system jurisdiction table, real-time transaction definition table, access process execution sequence table, real-time transaction nesting table, access relations table, child transaction table and so on. The twelve tables use storage structure of cross chain table and chain table.Data dictionary is the most frequent query part in the database system.The database system's found, movement and maintenance cannot leave data dictionary's support.Data dictionary records the entire database system resources description information. When the system resources are changed, data dictionary is also changed accordingly, including increase, deletion and revision.Using the cross chain table and the chain table structure, a data dictionary management prototype system is researched and constructed. It provides a series of functions to satisfy data dictionary's foundation, use, and maintenance's simulation.