mz_adapter::optimize::dataflows

Function prep_scalar_expr

Source 
pub fn prep_scalar_expr(
    expr: &mut MirScalarExpr,
    style: ExprPrepStyle<'_>,
) -> Result<(), OptimizerError>
Expand description

Prepares a scalar expression for execution by handling unmaterializable functions.

How we prepare the scalar expression depends on which style is specificed.

  • OneShot: Calls to all unmaterializable functions are replaced.
  • Index: An error is produced if a call to an unmaterializable function is encountered.
  • AsOfUpTo: An error is produced if a call to an unmaterializable function is encountered.
  • WebhookValidation: Only calls to UnmaterializableFunc::CurrentTimestamp are replaced, others are left untouched.