GB/T 17645.20-2002
Industrial automation systems and integration--Parts library--Part 20:Logical resource:Logical model of expressions (English Version)

Standard No.: GB/T 17645.20-2002
Language: Chinese, Available in English version
Release Date: 2002
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 17645.20-2002

Scope: This part of GB/T 17645 stipulates: - The EXPRESS mode of general expressions; - The EXPRESS mode of expressions establishes a subset of expressions allowed by the EXPRESS language, corresponding to the ones defined in IS0 10303-11:1994 Integer, Real, Boolean, and String. This pattern uses the resources defined in the common expression pattern. This part of GB/T 17645 is applicable to: - the exchange of expressions including constants and variables; - the function of checking whether a numerical expression should calculate an integer value; - the constraints to ensure that the expression is semantically correct ; - calculation of variables or functions used in the expression; - checking whether the expression can be mapped to a function of the SQL query language. This part of GB/T 17645 does not apply to: - Assignment of variables in some relevant environment; - Trigger mechanism for calculating the value of an expression in a given relevant environment.

GB/T 17645.20-2002 history

2002 GB/T 17645.20-2002 Industrial automation systems and integration--Parts library--Part 20:Logical resource:Logical model of expressions