R:BASE 11 Help

The following list describes the automatic table and database locks used in transaction processing.

 

Transaction Processing Locks

 

•SELECT table lock

 

 

These commands only need to view data from a table. A SELECT lock excludes all other locks except other SELECT locks.

 

 

•INSERT table lock

 

 

These commands may add a row to a table. An INSERT lock excludes all other locks.

 

 

•UPDATE table lock

 

 

These commands update information in a table. An UPDATE lock excludes all other locks.

 

 

•Full database lock

 

 

A full database lock excludes locks on all tables and the database and disables the LIST command until the transaction is finished. If a command cannot lock all the tables in a database, you receive a message.

 

The commands are listed under the lock they obtain most frequently. The current use of each command, however, determines which lock it obtains. These commands can only upgrade their locks within a transaction.

 

Transaction Processing Topics:

 

Using Transaction Processing

Locking Table Access and Resource Waiting

Row Locks and Transaction Processing

Setting Exclusive Table Locks

Displaying Transaction Processing Locks

Resource Waiting in Transaction Processing

Generate a Transaction Journal

Recovering from Transaction Processing Errors