UPDATE Statement

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3. Structured Query Language (SQL)
4. UPDATE Statement

Introduction

The SQL UPDATE statement modifies one or more rows in a database table. The format of the UPDATE statement is:

update-statement ::=
  UPDATE table-name
  SET set-clause-list
  [WHERE search-condition ]

Remarks

In Fernhill SCADA, the UPDATE Statement can only be used modify these tables:

• Any column in a Database Table Tag.
• The Value column of a Data Point Tag table.

When updating a Database Table Tag, the table-name must be qualified by the schema name DatabaseTable.

It is an error if a value in the set-clause-list results in string truncation.

If you need to limit the length of a string to fit a column, use the SUBSTRING() Function.

Examples

1. Write a value to the Internal Analog Data Point Tag called 'Analog_01':

   UPDATE InternalAnalog 
   SET Value = 2 
   WHERE FullName = 'Analog_01'

Further Information

Fernhill SCADA .NET Framework Data Provider

To learn about the .NET Framework Data Provider for Fernhill SCADA (FernhillSoftware.Data.FernhillScadaClient).

ODBC driver

To learn about the ODBC driver in Fernhill SCADA.

SQL Test Tool

To learn about the SQL Test Tool.

Glossary

For the meaning of terms used in Fernhill SCADA.

Fernhill SCADA Version 3.91 (20230201.2). Copyright © 2012-2023 Fernhill Software Ltd: All rights reserved.