BIP2421
Severity
20 : Error
Message
(<insert_1>, <insert_2>) : Left hand operand to <insert_3> operator must be a scalar.
Explanation
The left hand operand to the operator was not a scalar valued expression.
Response
Correct the syntax of your ESQL expression in node <insert_1>, around line and column <insert_2>, then redeploy the message flow: Ensure that the left hand operator to the <insert_3> operator is a scalar.