Function Based Index and java.lang.String

[Min-Koo Seo]

Hi.

I have a java stored procedure whose spec is as follows:

CREATE OR REPLACE FUNCTION DECODE_SEQUENCE(SEQUENCE VARCHAR2) RETURN
VARCHAR2
DETERMINISTIC
AS LANGUAGE JAVA
NAME 'kr.ac.dke.protein.compression.SequenceCompressor. decode(java.lang.String)
return java.lang.String';
/

AND I want to make an index like below:

CREATE INDEX K0_IDX ON K0(DECODE_SEQUENCE(TYPESTR), TYPELEN)
NOLOGGING
COMPRESS 2
/

However, above statement raises an error, saying that 'Maximum size of
index field is excceded.' Hence, I've changed the index creation
statement.

CREATE INDEX K0_IDX ON K0(SUBSTR(DECODE_SEQUENCE(TYPESTR),1,1),
TYPELEN)
NOLOGGING
COMPRESS 2
/

This works.

Here's the question. Can't I create an index on java.lang.String
without using SUBSTR function?

Regards,
Minkoo Seo

[Jim Kennedy]

"Min-Koo Seo" <po******@hanmail.net> wrote in message
news:4c**************************@posting.google.c om...

Hi.

I have a java stored procedure whose spec is as follows:

CREATE OR REPLACE FUNCTION DECODE_SEQUENCE(SEQUENCE VARCHAR2) RETURN
VARCHAR2
DETERMINISTIC
AS LANGUAGE JAVA
NAME 'kr.ac.dke.protein.compression.SequenceCompressor. decode(java.lang.String) return java.lang.String';
/

AND I want to make an index like below:

CREATE INDEX K0_IDX ON K0(DECODE_SEQUENCE(TYPESTR), TYPELEN)
NOLOGGING
COMPRESS 2
/

However, above statement raises an error, saying that 'Maximum size of
index field is excceded.' Hence, I've changed the index creation
statement.

CREATE INDEX K0_IDX ON K0(SUBSTR(DECODE_SEQUENCE(TYPESTR),1,1),
TYPELEN)
NOLOGGING
COMPRESS 2
/

This works.

Here's the question. Can't I create an index on java.lang.String
without using SUBSTR function?

Regards,
Minkoo Seo

It doesn't know how large a key is and a key cannot be larger than half a db
block. But with substring the key cannot exceed half a database block.
Jim