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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

Vision Client, Perspective Session


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

Gateway

Code Examples
Example - Clear Named Query Cache for a Specific Project
# 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 Named Query Cache
# 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)
Keywords

system db clearNamedQueryCache, db.clearNamedQueryCache  

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