Function render_procedure_as 

pub fn render_procedure_as(
    form: ProcedureForm,
    routine: &RoutineSpec,
    describes_procedures: bool,
) -> String

Spell this procedure in a named grammar.

The grammar a dialect is nearly the same as, written out, so a dialect that answers ProcedureForm::Custom can start from it and say what differs instead of writing a CREATE from nothing.

Parameters:

• form: the grammar to spell it in. Custom is not an error to pass — it answers with the agnostic form under a comment naming the grammar, so a fallback branch that reaches here gets something to read. ClickHouse and Databricks do the same, because neither deploys a procedure as SQL;
• routine: the procedure, in the shape a Custom dialect receives it;
• describes_procedures: the dialect’s own DdlRenderer::supports_procedure_comment. false leaves the routine’s description out, whatever the form, so an engine that has no statement for it is never handed one.