mysql> SELECT * FROM tabla;
+----------+------------+-----------+-------------+
| articulo | nombre_art | proveedor | nombre_prov |
+----------+------------+-----------+-------------+
| 1 | A | 1A | JUAN |
| 1 | A | 2A | JOSE |
| 1 | A | 3A | PEDRO |
| 2 | B | 1B | LUIS |
| 2 | B | 2B | RUBEN |
| 2 | B | 3B | OMAR |
| 3 | C | 1C | JOSUE |
| 3 | C | 2C | FELIPE |
| 3 | C | 3C | ROBERTO |
+----------+------------+-----------+-------------+
9 rows in set (0.00 sec)
mysql> SELECT * FROM tabla WHERE proveedor LIKE '1%';
+----------+------------+-----------+-------------+
| articulo | nombre_art | proveedor | nombre_prov |
+----------+------------+-----------+-------------+
| 1 | A | 1A | JUAN |
| 2 | B | 1B | LUIS |
| 3 | C | 1C | JOSUE |
+----------+------------+-----------+-------------+
3 rows in set (0.00 sec)
mysql> SELECT * FROM tabla WHERE proveedor LIKE '2%';
+----------+------------+-----------+-------------+
| articulo | nombre_art | proveedor | nombre_prov |
+----------+------------+-----------+-------------+
| 1 | A | 2A | JOSE |
| 2 | B | 2B | RUBEN |
| 3 | C | 2C | FELIPE |
+----------+------------+-----------+-------------+
3 rows in set (0.00 sec)
mysql> SELECT * FROM tabla WHERE proveedor LIKE '3%';
+----------+------------+-----------+-------------+
| articulo | nombre_art | proveedor | nombre_prov |
+----------+------------+-----------+-------------+
| 1 | A | 3A | PEDRO |
| 2 | B | 3B | OMAR |
| 3 | C | 3C | ROBERTO |
+----------+------------+-----------+-------------+
3 rows in set (0.00 sec)