[General]TagDB

Determines whether the Variable Tags database is loaded at runtime. The Variable Tags database needs to be loaded to allow tags to be referenced with the Equipment.Item syntax, as well as, to obtain the tag list shown by the TagDebug function, for Instant trends, if you are performing CtAPI ctFindFirst requests on the TAG table, for Super Genie associations and if you are using functions such as TagInfo, TagScaleStr and AssScaleStr.

If you do not need to use any of these features, you can save memory by disabling this parameter. Because the information needs to be loaded into memory, this parameter can use a large amount of memory. The amount of memory used by one tag is 30 bytes + the length of the name + 1. If you have 10,000 tags with an average name length of 16 characters, this parameter will use (30 + 16 + 10) x 10,0000 = 470,000 bytes. This memory usage would only be a problem if you are low on memory or have many variables.

Allowable Values:

• 0 - Disable variable tag database load

• 1 - Enable variable tag database load

Default Value:

1

Note: Plant SCADA can automatically resolve tags without a cluster context being specified if every tag name in the project is unique. However, this feature will only function correctly if this parameter is set to 1 (enabled). Confirm that this feature is not required before you disable this parameter.

See Also

General Parameters