system.db.runScalarPrepQuery

This function is used in Python Scripting.

Description

Runs a prepared statement against a database connection just like the runPrepQuery function, but only returns the value from the first row and column. If no results are returned from the query, the special value None is returned.

Client Permission Restrictions

Permission Type: Legacy Database Access

Client access to this scripting function is blocked to users that do not meet the role/zone requirements for the above permission type. This function is unaffected when run in the Gateway scope.

Syntax - Gateway

system.db.runScalarPrepQuery(query, args, database, [tx])

Parameters

Type	Parameter	Description
String	query	A SQL query (typically a SELECT) to run as a prepared statement with placeholders (?) denoting where the arguments go, that should be designed to return one row and one column.
List[Any]	args	A list of arguments. Will be used in order to match each placeholder (?) found in the query.
String	database	The name of the database connection to execute against.
String	tx	A transaction identifier. If omitted, the query will be executed in its own transaction. [optional]

Returns

Any - The value from the first row and first column of the results. Returns None if no rows were returned.

Scope

Gateway

Syntax - Vision and Perspective

system.db.runScalarPrepQuery(query, args, [database], [tx])

Parameters

Type	Parameter	Description
String	query	A SQL query (typically a SELECT) to run as a prepared statement with placeholders (?) denoting where the arguments go, that should be designed to return one row and one column.
List[Any]	args	A list of arguments. Will be used in order to match each placeholder (?) found in the query.
String	database	The name of the database connection to execute against. If omitted or "", the project's default database connection will be used. [optional]
String	tx	A transaction identifier. If omitted, the query will be executed in its own transaction. [optional]

Returns

Any - The value from the first row and first column of the results. Returns None if no rows were returned.

Scope

Vision Client, Perspective Session

Code Examples

Code Snippet - Executing Query

# This example searches for the user id of someone based on a typed in username.
name = event.source.parent.getComponent("User Search").text
 
result = system.db.runScalarPrepQuery("SELECT user_id FROM users WHERE username = ?", [name])
event.source.parent.getComponent("Text Field").data = result

Keywords

system db runScalarPrepQuery, db.runScalarPrepQuery