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The following feature is new in Ignition version 7.9.6
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This function is used in Python Scripting.

Description

This clears the cache of a Named Query. If called from the Shared Scope (i.e., Tag Event Scripts, Alarm Pipelines, etc.) then the name of the project must be passed as a parameter.

Client Permission Restrictions

This scripting function has no Client Permission restrictions.

Syntax - Project Scope

system.db. clearNamedQueryCache(path)

  • Parameters

String  path - The Path to the named query we want to clear the cache of.

  • Returns

No Return Value

  • Scope

All

Syntax - Shared Scope

system.db. clearNamedQueryCache(project, path)

  • Parameters

String  project - The Project that contains the named query whose cache needs to be cleared.

String  path - The Path to the named query we want to clear the cache of.

  • Returns

No Return Value

  • Scope

All

Code Examples
Simple Example
# Calling this simply clears all Named Query Caches. 
# This example is being called from the Shared Scope. If called from the Project Scope, the projectName parameter should be omitted. 


projectName = "myProject"
namedQueryPath = "folder/selectFromInventory"

system.db.clearNamedQueryCache(projectName, namedQueryPath)
Example - Clear Custom NQ Calls
# If the same Named Queried is called multiple times with different parameters in a single script, then we can clear the caches once we're done with the following.
# This example assumes the script is running in the Project Scope. If called from the Shared Scope, the name of the project would need to be included. 

namedQueryPath = "myUpdateQuery"

# This creates one cache.
params = {"param1":"A"}
system.db.runNamedQuery(namedQueryPath, params)

# This creates a separate cache.
params = {"param1":"B"}
system.db.runNamedQuery(namedQueryPath, params)

# Clear all of the caches from the specified Named Query. Note that all caches are cleared, including those generated from elsewhere on the Gateway. 
system.db.clearNamedQueryCache(namedQueryPath)
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