PLC Database Access via Structure Tag Translation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Engineers responsible for control programs for programmable logic controllers (PLCs) and other control devices face difficulties in operating databases, as they are not familiar with database operations, particularly in writing SQL statements.
Innovation Solution
A control device equipped with a memory, generator, and execution unit that stores user programs and definition information, generating SQL statements based on structure types of variables, allowing access to a database system without requiring expertise in SQL operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If engineers use traditional database operations with SQL statements, then database access functionality is achieved, but programming complexity increases and ease of operation deteriorates
Solution Approach 1:
The patent introduces an intermediary mechanism (the control device's database access function) that translates between the familiar structure tag notation used by control engineers and SQL statements required by database systems. This intermediary handles the conversion automatically, allowing engineers to program using structure tags while the system generates and executes the corresponding SQL statements behind the scenes.
Solution Approach 2:
The control device performs self-service by automatically generating SQL statements from structure tag definitions without requiring external intervention or manual SQL writing. The system reads the structure tag definitions, generates the appropriate SQL statements, and executes them against the database system autonomously, freeing engineers from learning SQL syntax.
2Adaptability or versatility
If engineers are required to learn SQL statements for database access, then database operation capability is improved, but learning curve and time consumption increase
Solution Approach 1:
The patent employs an intermediary translation layer that converts structure tag definitions into SQL statements automatically. This mediator handles the adaptation between the engineer's familiar control programming paradigm and the database system's SQL requirements, eliminating the need for engineers to learn SQL while maintaining full database operation capability.
Solution Approach 2:
The control device achieves universality by making structure tags serve multiple functions: they continue to represent control variables as before, and simultaneously serve as the basis for automatic SQL statement generation. This multi-functionality allows the same structure tag system to work for both control logic and database access without requiring separate SQL learning.
3Adaptability or versatility
If control engineers focus on control program structures, then control programming expertise is maintained, but database operation knowledge is lost
Solution Approach 1:
The patent introduces a mediator that translates control engineers' structure tag definitions into database access commands. This intermediary allows engineers to maintain their focus on control program structures using familiar structure tags, while the system automatically handles the translation to SQL and execution of database operations, making database operations as easy as control variable definitions.
Data Source
AI summary
Provided is a technique enables programming, including that for database operations, without describing a SQL used to operate the database. A PLC (30) that can access a DBMS (22) stores a user program (38) and definition information (32), the user program (38) including a structure type of variable, the definition information (32) indicating a definition of the structure type. The sequence command program (34) sequentially executes instructions in the user program (38) and invokes a DB access process program (35) in order to access the DBMS (22). The DB access process program (35) reads the definition information (32) and, on the basis of the read definition information (32), generates a SQL statement to be used when access to the DBMS (22) is made by execution of the user program (38). The DB access process program (35) executes the generated SQL statement by transmitting the SQL statement to the DB server (20).