# `CALC_MATERIALS_SMAIL` (function)

> 两变都小于305的材料（单位CM）


- **Type:** FUNCTION
- **Returns:** `decimal(18,6)`
- **Deterministic:** NO
- **SQL data access:** CONTAINS SQL

## Parameters

| # | Mode | Name | Type |
|---|---|---|---|
| 1 | IN | `dQty` | `decimal(18,6)` |
| 2 | IN | `dWidth` | `decimal(18,6)` |
| 3 | IN | `dLength` | `decimal(18,6)` |

## Body

_Body is not pre-cached. To inspect: `mysql --defaults-file=~/.my.cnf -e 'SHOW CREATE FUNCTION `CALC_MATERIALS_SMAIL`'`._

## Narrative

**Business context:** Material yield estimator for cuts taken from a stock board capped at 305 cm per side (board dimensions in cm). Header comment is `两变都小于305的材料（单位CM）` ("both sides under 305, unit CM"). Counts how many 305-cm stock boards a batch of `dQty` pieces of size `dWidth × dLength` will consume, including offcut reuse.

**What it does:** sorts the long/short side, peels off any "whole-board" multiples when a side exceeds 305, then loops the remaining pieces along a 305-cm running cutline and uses a JSON list to track usable offcuts (`料头`). Returns the total board count. Does not read or write any table — pure arithmetic.

**Invocation:** Status: appears orphaned. No caller found in any channel (form-master sSqlStr, gdsmodule hooks, other routines, exhaustive xly-src grep, dynamic-dispatch search) — candidate for maintainer audit.