Server User Manual

Appendix G Exclusive Control between
Application Programs and RDB Commands
When an application program and RDB command operate simultaneously on the same database resource, the
SymfoWARE/RDB system performs exclusive control. In this way, each process can be executed without
contradiction.
Each function performs processing by applying exclusive control of the resource specified by the option or input data.
The period for which the resource is exclusively controlled is as follows:
Application program:
From the time the first SQL statement is issued from the application program until the application program
terminates
RDB command:
From the time the command is entered until the response message is generated
Table: Locked resources and locked strength for each SymfoWARE/RDB function shows resources for which
lock is performed by each function and the strength of the lock. Table: Relationships among lock strengths
shows the relationships among locked strengths.
[Table: Locked resources and locked strength for each SymfoWARE/RDB function]
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