Method Eval

pkg/sql/sem/tree/eval.go:4082–4115

Eval implements the TypedExpr interface.

(ctx *EvalContext)

// Eval implements the TypedExpr interface.
func (expr *FuncExpr) Eval(ctx *EvalContext) (Datum, error) {
	nullResult, args, err := expr.evalArgs(ctx)
	if err != nil {
		return nil, err
	}
	if nullResult {
		return DNull, err
	}

	res, err := expr.fn.Fn(ctx, args)
	if err != nil {
		// If we are facing an explicit error, propagate it unchanged.
		fName := expr.Func.String()
		if fName == `crdb_internal.force_error` {
			return nil, err
		}
		// Otherwise, wrap it with context.
		newErr := errors.Wrapf(err, "%s()", errors.Safe(fName))
		// Count function errors as it flows out of the system.  We need
		// to have this inside a if because if we are facing a retry
		// error, in particular those generated by
		// crdb_internal.force_retry(), Wrap() will propagate it as a
		// non-pgerror error (so that the executor can see it with the
		// right type).
		newErr = errors.WithTelemetry(newErr, fName+"()")
		return nil, newErr
	}
	if ctx.TestingKnobs.AssertFuncExprReturnTypes {
		if err := ensureExpectedType(expr.fn.FixedReturnType(), res); err != nil {
			return nil, errors.NewAssertionErrorWithWrappedErrf(err, "function %q", expr)
		}
	}
	return res, nil
}

// ensureExpectedType will return an error if a datum does not match the
// provided type. If the expected type is Any or if the datum is a Null