opening a small screen (3x2) results in redundant queries :

Time:0.00037 SQL: SELECT * FROM screens_items WHERE screenid=3
Time:0.000275 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=0 AND y=0
Time:0.00025 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=1 AND y=0
Time:0.000241 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=2 AND y=0
Time:0.000237 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=0 AND y=1
Time:0.000246 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=2 AND y=1
Time:0.000287 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=0 AND y=0
Time:0.00033 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=1 AND y=0
Time:0.000328 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=2 AND y=0
Time:0.000341 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=0 AND y=1
Time:0.000918 SQL: SELECT * FROM screens_items WHERE screenid=3 AND x=2 AND y=1

even if the first query can't return all the needed data in one go, there are at least 6 duplicated queries out of 10