cpotextamnd

### 1) Overview
 The `cpotextamnd` table serves as a historical repository for descriptive text or special instructions associated with **Central Purchase Order (CPO) amendments**. While the base PO text is typically stored in `cpotext`, this table captures the state of those details at each specific amendment level (`amendno`). It is a secondary detail table linked to the CPO amendment header.
 
 ### 2) Column Dictionary
 
 | Column | Type | Nullable | Meaning | Allowed Values | SQL Usage |
 | :--- | :--- | :--- | :--- | :--- | :--- |
 | **index** | integer | NO | Primary Key; internal row identifier. | 0, 1, 2... | `PK` |
 | **compcode** | string | NO | Company identifier code. | e.g., "DAS" | `JOIN`, `WHERE` |
 | **pono** | integer | NO | Purchase Order Number. | e.g., 118, 80 | `JOIN`, `WHERE` |
 | **amendno** | integer | NO | The specific amendment version number. | 0 = Initial, 1+ = Revisions | `JOIN`, `WHERE` |
 | **cpodetail** | string | YES | The actual long-form text or comments for the PO. | Text strings | `SELECT` |
 | **invyear** | integer | NO | The inventory or financial year associated with the PO. | e.g., 2014, 2015 | `JOIN`, `WHERE` |
 
 ### 3) Relationships & Join Map
 
 #### Logical Parents
 * **dbo.cpohdramnd**: The primary header for PO amendments. Join on `compcode`, `pono`, `amendno`, and `invyear` to get general amendment info (reasons, dates).
 * **dbo.cpohdr**: The original PO header. Join on `compcode`, `pono`, and `invyear` to see the current status of the root document.
 
 #### Logical Siblings
 * **dbo.cpodtlamnd**: Stores the line-item amendments (quantities, rates). Join on `compcode`, `pono`, `amendno`, and `invyear`.
 * **dbo.cpotext**: The current/base text for the PO. Join on `compcode`, `pono`, and `invyear`.
 
 #### Join Example (SQL Server)
 ```sql
 SELECT 
  h.pono, 
  h.amendno, 
  h.amenddate, 
  t.cpodetail
 FROM dbo.cpohdramnd h
 INNER JOIN dbo.cpotextamnd t 
  ON h.compcode = t.compcode 
  AND h.pono = t.pono 
  AND h.amendno = t.amendno 
  AND h.invyear = t.invyear
 WHERE h.pono = 80;
 ```