groupitem

### 1. Overview
 The `groupitem` table serves as a **Bill of Materials (BOM)** or **Kit Definition** mapping within the ERP system. It defines the relationship between a "Group" or "Assembly" item (represented by `groupcode`) and its constituent "Child" or component items (represented by `itemcode`). 
 
 In production logic (specifically within `FGStock` and `TotalItemStock` stored procedures), this table is used to calculate "Used in Assembly" quantities. When an assembly item is received via `goodreceipt`, the system references `groupitem` to determine the specific component items that were consumed to create that assembly.
 
 ### 2. Column Dictionary
 
 | Column | Type | Nullable | Meaning | Allowed Values | SQL Usage |
 | :--- | :--- | :--- | :--- | :--- | :--- |
 | **index** | integer | No | Primary key; unique record identifier. | | `PRIMARY KEY` |
 | **compcode** | string | No | Company code for multi-tenant isolation. | e.g., "DAS", "BAM" | `JOIN`, `WHERE` |
 | **groupcode** | string | No | The code representing the Parent Item, Kit, or Assembly. | e.g., "LERVERKVE" | `JOIN` (to `itemmas.itemcode` or `goodreceipt.itemcode`) |
 | **itemcode** | string | No | The code representing the Child Item or Component. | e.g., "CP-301" | `JOIN` (to `itemmas.itemcode`) |
 | **itemqty** | number | Yes | The quantity of the component required for one unit of the group. | e.g., 1.0, 2.5 | `SUM`, `CALCULATION` |
 
 ### 3. Relationships & Join Map
 
 Based on the `SCHEMA_MAP` and logic extracted from `REFERENCE_JSON`, the following joins are authoritative:
 
 #### Strict Physical Joins (SCHEMA_MAP Verified)
 * **dbo.itemmas**: Join on `compcode` and `itemcode`. Used to retrieve technical specifications (finish weight, name) for component items.
 * **dbo.groupmas**: Join on `compcode` and `groupcode`. Used to retrieve master details for the parent assembly group.
 * **dbo.goodreceipt**: Join `goodreceipt.itemcode` = `groupitem.groupcode`. This is used to explode assembly receipts into component consumption.
 * **dbo.invdtl**: Join on `compcode` and `itemcode`. Used to track which specific components are being moved or sold via parent groups.
 
 #### Logic Join Patterns
 ```sql
 -- Pattern used in FGStock to find components consumed for Assemblies
 SELECT 
  q.itemcode, 
  SUM(p.aqtystore * q.itemqty) as ComponentConsumed
 FROM dbo.goodreceipt p
 INNER JOIN dbo.groupitem q 
  ON p.itemcode = q.groupcode 
  AND p.compcode = q.compcode
 WHERE p.itemflag = 'A'; -- 'A' usually denotes Assembly in this context
 ```