rmjobhdr

### 1. Overview
 The `rmjobhdr` table serves as the header-level record for **Raw Material Job Work transactions**, specifically focusing on "Drawing" operations or secondary raw material processing performed by vendors or internal departments. It tracks the issuance of specific Raw Material (RM) lots (identified by `mrpno` and `lotno`) to external entities for transformation into a required material state (indicated by `rmcodereq`).
 
 The table captures essential operational data including weights, heat numbers, vehicle details, and unit conversions, alongside financial metadata such as GST tax breakdowns (`CGST`, `SGST`, `IGST`) and total invoice values. It is a critical component in the material ledger, linking initial raw material receipt (`rmincoming`) to subsequent job work processing records (`rmjobdtl`, `rmmrphdr`).
 
 ### 2. Column Dictionary
 
 | Column | Type | Nullable | Meaning | Allowed Values | SQL Usage |
 | :--- | :--- | :--- | :--- | :--- | :--- |
 | **index** | integer | No | Primary Key (Internal) | Auto-increment | `PRIMARY KEY` |
 | **compcode** | string | No | Company Code | e.g., 'DAS' | `JOIN`, `WHERE` |
 | **jobcardno** | integer | No | Unique Job Card Identifier | e.g., 20156 | `JOIN` (to `rmjobdtl`, `rmmrphdr`) |
 | **jobdate** | datetime | No | Date the Job Card was created | ISO Date | `WHERE`, `ORDER BY` |
 | **vendcode** | string | Yes | Vendor/Department processing the RM | e.g., 'BALAJI', 'RS' | `JOIN` (to `vendmas.vendcode`) |
 | **exciseno** | string | Yes | Document/Invoice Number | e.g., '6', 'JW/25-26/00009' | Filter by document |
 | **excisedate** | datetime | Yes | Date of the document/removal | ISO Date | Reporting |
 | **rmcode** | string | Yes | Original Raw Material Code issued | e.g., 'SCM42040' | `JOIN` (to `rmmas.rmcode`) |
 | **rmweight** | number | Yes | Total Weight of RM issued | e.g., 3160.0 | Aggregation (Issue Wt) |
 | **mrpno** | integer | Yes | RM Receipt/Batch Number | e.g., 1535 | `JOIN` (to `rmincoming.mrpno`) |
 | **lotno** | string | Yes | Production Lot Number | e.g., '4165' | Identification |
 | **rmcodereq** | string | Yes | Material Code required after processing | e.g., 'ROD39.50' | `JOIN` (to `rmmas.rmcode`) |
 | **heatno** | string | Yes | Heat/Batch number of the steel | e.g., 'M85511/7915' | Quality Tracking |
 | **puom** | string | Yes | Primary Unit of Measure | 'KGS' | Units |
 | **convqty** | number | Yes | Quantity in converted units | e.g., 3160.0 | Calculation |
 | **convuom** | string | Yes | Conversion Unit of Measure | 'KGS' | Units |
 | **convr** | number | Yes | Conversion Rate factor | e.g., 1.0 | Math |
 | **itemvalue** | number | Yes | Assessable value of the material | e.g., 252800.0 | Financials |
 | **CGST_Amt** | number | Yes | Central GST Amount | | Tax Reporting |
 | **SGST_Amt** | number | Yes | State GST Amount | | Tax Reporting |
 | **IGST_Amt** | number | Yes | Integrated GST Amount | | Tax Reporting |
 | **TotalAMt** | number | Yes | Grand total including taxes | | Billing |
 | **JobRGPFlag** | string | Yes | Job vs Returnable Gate Pass Flag | 'J' (Job), 'C' (RGP) | `WHERE` |
 | **doc** | string | Yes | Document reference string | | Search |
 | **close_flag** | string | Yes | Completion status | 'Y', NULL | Filter active jobs |
 | **Vehicle** | string | Yes | Vehicle number for transport | | Logistics |
 | **through** | string | Yes | Transporter/Person responsible | | Logistics |
 | **tpcode** | string | Yes | Transport Provider Code | | `JOIN` (to `transptmas.tpcode`) |
 | **rework_flag** | integer | Yes | Indicates if the job is for rework | 0, 1 | Logic |
 | **e_waybill_no** | string | Yes | GST E-Way Bill Number | | Statutory Compliance |
 
 ### 3. Relationships & Join Map
 
 #### Authoritative Physical Joins (via SCHEMA_MAP):
 * **rmjobdtl**: `rmjobhdr.jobcardno` → `rmjobdtl.jobcardno` (and `compcode`). Used to retrieve operation-wise details of the job.
 * **rmmrphdr**: `rmjobhdr.jobcardno` → `rmmrphdr.jobcardno` (and `compcode`). Used to track material receipt *back* from the vendor after job work completion.
 * **vendmas**: `rmjobhdr.vendcode` → `vendmas.vendcode` (and `compcode`). Used to get vendor name and address.
 * **rmmas**: 
  * `rmjobhdr.rmcode` → `rmmas.rmcode` (and `compcode`).
  * `rmjobhdr.rmcodereq` → `rmmas.rmcode` (and `compcode`).
 * **rmincoming**: `rmjobhdr.mrpno` → `rmincoming.mrpno` (and `compcode`). Links the job card back to the original stock purchase/receipt.
 * **billagainstwo**: `rmjobhdr.jobcardno` → `billagainstwo.jobno` (and `compcode`). Links job work to vendor billing and adjustments.
 * **transptmas**: `rmjobhdr.tpcode` → `transptmas.tpcode` (and `compcode`). Used for logistics documentation.
 * **mrprejhdr**: `rmjobhdr.jobcardno` → `mrprejhdr.jobno` (and `compcode`). Used for tracking rejections against job cards.
 
 #### Likely Logical Joins (Inferred):
 * **rmreturn**: `rmjobhdr.jobcardno` → `rmreturn.jobno` (and `compcode`). To track RM returned unused from a vendor.
 * **location**: `rmjobhdr.location` → `location.loccode` (and `compcode`). To identify physical stock locations.