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+# Stock Dashboard - MySQL Tables
+ 
+Exported from Omni Accounts Firebird database (`STARGASHO.FDB`).
+ 
+## Tables
+ 
+### products.sql — `STK_STOCKITEM`
+Product master table. One row per product/stock item.
+Key columns: `STOCKCODE`, `DESCRIPTION`, `CATEGORY`, `PRODUCTGROUP`, `UOM`, `COSTPRICE`, `SELLINGPRICE1`, `ISACTVE`
+ 
+### categories.sql — `STK_STOCKCATEGORY`
+Lookup table for product categories. Join `STK_STOCKITEM.CATEGORY` → `STCKCTGRYCDE`.
+Key columns: `STCKCTGRYCDE`, `STCKCTGRYDESC`
+ 
+### suppliers.sql — `PL_SUPPLIERACCOUNT`
+Supplier master table. One row per supplier account.
+Key columns: `SUPLCDE`, `SUPLNME`, address fields, contact fields
+ 
+### supplier_invoices.sql — `PL_BILL`
+Supplier invoice headers. One row per invoice received from a supplier.
+Key columns: `REFNO`, `ACCNO` (→ SUPLCDE), `DOCDTETME`, `SUPLNME`
+ 
+### supplier_invoice_lines.sql — `PL_BILLTRAN`
+Supplier invoice line items. One row per product line on a supplier invoice.
+Key columns: `REFNO` (→ PL_BILL), `STOCKCODE` (→ STK_STOCKITEM), `QTYTOINVOICE`, `COSTPRICE`
+ 
+### customers.sql — `SL_CUSTOMERACCOUNT`
+Customer/debtor master table. One row per customer account.
+Key columns: `DBTRCDE`, `DBTRNME`, `REGION`, `DBTRCTGRY`, `CRLMT`
+ 
+### customer_invoices.sql — `SL_SALESINVOICE`
+Customer invoice headers. One row per invoice issued to a customer.
+Key columns: `REFNO`, `ACCNO` (→ DBTRCDE), `DOCDTETME`, `DBTRNME`
+ 
+### customer_invoice_lines.sql — `SL_SALESINVOICETRAN`
+Customer invoice line items. One row per product line on a customer invoice.
+Key columns: `REFNO` (→ SL_SALESINVOICE), `STOCKCODE` (→ STK_STOCKITEM), `QTYTOINVOICE`, `SELLINGPRICE`, `COSTPRICE`
+ 
+## Joining the Tables
+ 
+**Supplier purchases per product:**
+```sql
+SELECT p.DESCRIPTION, s.SUPLNME, il.QTYTOINVOICE, il.COSTPRICE, i.DOCDTETME
+FROM supplier_invoice_lines il
+JOIN supplier_invoices i ON il.REFNO = i.REFNO
+JOIN suppliers s ON i.ACCNO = s.SUPLCDE
+JOIN products p ON il.STOCKCODE = p.STOCKCODE;
+```
+ 
+**Customer sales per product:**
+```sql
+SELECT p.DESCRIPTION, c.DBTRNME, il.QTYTOINVOICE, il.SELLINGPRICE, i.DOCDTETME
+FROM customer_invoice_lines il
+JOIN customer_invoices i ON il.REFNO = i.REFNO
+JOIN customers c ON i.ACCNO = c.DBTRCDE
+JOIN products p ON il.STOCKCODE = p.STOCKCODE;
+```
+ 
+ 
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