SELECT name FROM `table1` WHERE id IN(4,5,6,7,7,7);
SELECT name FROM `table1` WHERE id IN(4,5,6,7)
UNION ALL
SELECT name FROM `table1` WHERE id IN(7)
UNION ALL
SELECT name FROM `table1` WHERE id IN(7)+---------------------------+
| name |
+---------------------------+
| name4 |
| name5 |
| name6 |
| name7 |
+---------------------------++---------------------------+
| name |
+---------------------------+
| name4 |
| name5 |
| name6 |
| name7 |
| name7 |
| name7 |
+---------------------------+
Только в IN(4,5,6,7,7,7) всегда разное количество данных, может дойти и до 5к