Controller, information processing apparatus, and recording medium

A computer-readable recording medium storing a computer program executable by a processor and configured to control operation of a controller, wherein

• the controller comprises a communication interface configured to access a database system, the processor, and a memory, and
• the program causes the processor to execute:
• a step of executing a user program to control a control object;
• and
• a step of, at the time of executing the user program including an access instruction to access the database system, controlling an access to the database system via the communication interface by a statement according to the access instruction,
• a step of controlling an access to the database system by the statement according to the access instruction is performed in the first and second modes, and the program causes the processor to perform a step of
• in the first mode, transmitting a statement according to the access instruction to the database system and sending the result of response of the statement to the user program, and
• in the second mode, sending the result of execution corresponding to the statement to the user program without transmitting the statement to the database system.

An information processing apparatus to be connected to a controller, wherein

• the controller comprises:
• a communication interface configured to be connected to a database system;
• an instruction executing unit configured to execute a user program for controlling a control object;
• an access processing unit, at the time of executing the user program including an access instruction for accessing the database system by the instruction executing unit, configured to control an access via the communication interface to the database system by a statement according to the access instruction;
• and
• an input/output unit configured to be connected to the information processing apparatus and to transmit/receive data to/from the information processing apparatus,
• the access processing unit operates in a first mode and a second mode,
• in the first mode, transmits a statement according to the access instruction to the database system and sends a result of a response to the statement to the user program, and
• in the second mode, sends a result of execution corresponding to the statement to the user program without transmitting the statement to the database system, and
• the information processing unit comprises:
• a reception processing unit configured to receive a result of a response to the user program by the access processing unit via the input/output unit of the controller;
• and
• a display processing unit configured to display the response result received by the reception processing unit on a monitor.

A controller comprising:

• a communication interface configured to be connected to a database system;
• a processor;
• and
• a memory, wherein
• the processor is configured to operate while switching a first mode and a second mode, executes a user program for controlling a control object, at the time of the execution of the user program including an access instruction to access the database system, controls an access via the communication interface to the database system by a statement according to the access instruction, in the case of operation in the first mode, transmits the statement according to the access instruction to the database system, sends a result of response to the statement to the user program, in the case of operation in the second mode, sends a result of execution corresponding to the statement to the user program without transmitting the statement to the database system.