Case sensitivity in Oracle Text

Question

I am familiar with the mixed_case parameter, and in my setup it is set to no, so all searches are case-insensitive. This is what I want 95% of the time, but is there a way to specify (at a query level) that a contains search is case sensitive?

Answer 1

Hi,
Would be nice, but the tokens are converted to uppercase on indexing. For example:
SQL> create table test (col1 varchar2(20));
Table created.
SQL> insert into test values ('MixEd cAsE');
1 row created.
SQL> create index test_idx on test(col1)
2 indextype is ctxsys.context;
Index created.
SQL> select token_text from dr$test_idx$i;
TOKEN_TEXT
CASE
MIXED
So, since they are actually stored/converted to uppercase there is nothing case-sensitive for your query to compare to.
On the flip side, if you index case-sensitive, the tokens are stored mixed-case.
SQL> drop index test_idx force;
Index dropped.
SQL> begin
2 ctx_ddl.create_preference('mylex', 'BASIC_LEXER');
3 ctx_ddl.set_attribute('mylex', 'mixed_case', 'yes');
4 end;
5 /
PL/SQL procedure successfully completed.
SQL> create index test_idx on test(col1)
2 indextype is ctxsys.context
3 parameters('lexer mylex');
Index created.
SQL> select token_text from dr$test_idx$i;
TOKEN_TEXT
MixEd
cAsE
Now you can do something with your query to make it do what you want. You'd have to check performance to see if it is worth it.
Ron