Pocket Access - III

Pocket Access files are essentially mounted CEDB volumes with a very specific structure. They all contain four system tables:

• MSysFields - Contains all the columns of all tables in the database, including the columns of the system tables.


• MSysTables - Contains all the tables in the database, including the system tables themselves.


• MSysIndexes - User indexes are all declared here.


• MSysProcs - Stored procedures?

An empty Pocket Access database has all four tables created and the first two have some information: the system metadata. System tables are all created as type 3 (see below) and none contains a sort order with the exception of MSysFileds which has a sort order (type 0 - undocumented) on column zero.

To create a Pocket Access database, we must create all system tables an fill them with their default values. This process must be done in a very specific order: 1 - Mount a new CEDB volume; 2 - Create the databases and store their OIDs (the preferred order of creation is MSysFields, MSysTables, MSysIndexes, MSysProcs); 3 - Fill the MSysFields database; 4 - Fill the MSysTables database.

Each record on the MSysFields database has 5 columns (names taken from MSysFields itself):

• TableID - (int) Table OID


• FieldName - (string) Field name


• FieldID - (int) Field property id


• Len - (short) Field length


• ODBCType - (short) Data type

The MSysTables table contains only 3 columns:

• TableName - (string) Table name


• TableID - (int) Table OID


• TableFlags - (int) Table flags (system tables = 3, user = 0)

MSysIndexes has the following columns:

• TableID - (int) Table OID


• IndexName - (string) Index name


• FieldID - (int) Field property id


• IndexFlags - (int) CEDB sort order flags