Attribute Macro admin_fn 

#[admin_fn]

Attribute macro to convert a normal function to SQL administration function. The annotated function should accept:

• &ProcedureServiceHandlerRef or &TableMutationHandlerRef or FlowServiceHandlerRef as the first argument,
• &QueryContextRef as the second argument, and
• &[ValueRef<'_>] as the third argument which is SQL function input values in each row.

Return type must be common_query::error::Result<Value>.

Example see common/function/src/system/procedure_state.rs.

Arguments

• name: The name of the generated Function implementation.
• ret: The return type of the generated SQL function, it will be transformed into ConcreteDataType::{ret}_datatype() result.
• display_name: The display name of the generated SQL function.
• sig_fn: the function to returns Signature of generated Function.
• user_path: Optional path to the trait and context (e.g., crate); defaults to crate if not provided.