Postgres 16

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create table table1 (Field1,	field2) as values
 ('a','INSERT INTO table2_insert_target{ name, age, city, id}
       SELECT name, age, city, id FROM table1_select_source')
,('b','select from table3_select_source')
,('c','select * from table4_select_source')
,('d','delete from table5_delete_target using table6_delete_source')
,('e','update table7_update_target from table8_update_source')
,('f','table table9_table_expression')
,('g','select table10_not_unpacked from table10_not_unpacked')
,('h','SELECT $$abc$$ InTo table11_select_into_target;')
,('i','select * from only table12_from_only;')
,('j','select * from table13_join1 join table14_join2 on true')
,('k','select * from (table table14_table_expression_in_subquery);')
,('l','select * from "table15_double_quoted"')
,('m','select * from only "select * from table16_problems,, !@$@%#%#^@&%;;''"')
,('n','select * from only "select * from table17_multiple_problems,, !@$@%#%#^@&%;;''", "table18_more_problems_if_greedy: THIS SHOULD NOT BE A PART OF table17"')
,('o','select * from only """"')
,('p','select * from only "table19_comma_separated1", "table20_comma_separated2", "table21_comma_separated3"')
,('q','select * from only "table22_comma_separated1", (select from table23_in_comma_separated_subquery) as x, "table24_double_quoted_after_subquery"')
,('r','select * from only "table25_comma_separated1" as "table28_alias", (select from table26_in_comma_separated_subquery) as x, table27_unquoted_after_subquery')
  ;
/*  
Field1	field2
a	table2
b	table3
c	table4
*/

SELECT 18

field1	spotted_table	origin_query
a	table2_insert_target	INSERT INTO table2_insert_target{ name, age, city, id} SELECT name, age, city, id FROM table1_select_source
a	table1_select_source	INSERT INTO table2_insert_target{ name, age, city, id} SELECT name, age, city, id FROM table1_select_source
b	table3_select_source	select from table3_select_source
c	table4_select_source	select * from table4_select_source
d	table5_delete_target	delete from table5_delete_target using table6_delete_source
d	table6_delete_source	delete from table5_delete_target using table6_delete_source
e	table7_update_target	update table7_update_target from table8_update_source
e	table8_update_source	update table7_update_target from table8_update_source
f	table9_table_expression	table table9_table_expression
g	table10_not_unpacked	select table10_not_unpacked from table10_not_unpacked
h	table11_select_into_target	SELECT $$abc$$ InTo table11_select_into_target;
i	table12_from_only	select * from only table12_from_only;
j	table13_join1	select * from table13_join1 join table14_join2 on true
j	table14_join2	select * from table13_join1 join table14_join2 on true
k	table14_table_expression_in_subquery	select * from (table table14_table_expression_in_subquery);
l	"table15_double_quoted"	select * from "table15_double_quoted"
m	"select * from table16_problems,, !@$@%#%#^@&%;;'"	select * from only "select * from table16_problems,, !@$@%#%#^@&%;;'"
n	"select * from table17_multiple_problems,, !@$@%#%#^@&%;;'"	select * from only "select * from table17_multiple_problems,, !@$@%#%#^@&%;;'", "table18_more_problems_if_greedy: THIS SHOULD NOT BE A PART OF table17"
o	only	select * from only """"
p	"table19_comma_separated1"	select * from only "table19_comma_separated1", "table20_comma_separated2", "table21_comma_separated3"
q	"table22_comma_separated1"	select * from only "table22_comma_separated1", (select from table23_in_comma_separated_subquery) as x, "table24_double_quoted_after_subquery"
q	table23_in_comma_separated_subquery	select * from only "table22_comma_separated1", (select from table23_in_comma_separated_subquery) as x, "table24_double_quoted_after_subquery"
r	"table25_comma_separated1"	select * from only "table25_comma_separated1" as "table28_alias", (select from table26_in_comma_separated_subquery) as x, table27_unquoted_after_subquery
r	table26_in_comma_separated_subquery	select * from only "table25_comma_separated1" as "table28_alias", (select from table26_in_comma_separated_subquery) as x, table27_unquoted_after_subquery

SELECT 24