Two Novice Questions

Please forgive me if the following two questions are rather elementary for this group; however, as far as I can tell, this is the only relevant group to which we have access.

We are running ORACLE RDBMS V6.0.30.3.1 on a Sun SPARCstation 2 (4/75) under SunOS 4.1.1. The binaries are actually NFS mounted from a Sun 4/330 server while the data is stored on a local disk.

I am the UNIX system administrator for both systems but know next to nothing about Oracle per se. Our Oracle DBA is not conversant with USENET and is not especially receptive to suggestions for optimizing our setup, so I am posting this partly on her behalf and partly for my own information. Any suggestions and/or clarifications would be greatly appreciated.

Question #1: When executing reports (SQL*Reportwriter) we receive the message "Oracle Error occurred: ORA-02112: PCC: Select..Into returns too many rows." But when we execute it a second time it works fine. Can anyone explain this behavior?

Question #2: We would like to understand what to expect in the way of disk consumption for a given size database. In particular, we are running out of disk space and we need to know whether or not we can compact the current data structure. For example, here is a listing of our current data directory on the SS2 local disk:

total 94414
-rw------- 1 oracle 5120 Mar 6 13:53 alpha_seq_92.rep
-rw------- 1 oracle 10487808 Mar 9 11:24 camelot_space
-rw------- 1 oracle 20973568 Mar 9 13:13 carol_space
-rw------- 1 oracle 29184 Mar 9 11:24 control_file
-rw------- 1 oracle 187 Aug 7 1991 glogin.sql
-rw------- 1 oracle 10487808 Mar 9 13:14 index_space
-rw------- 1 oracle 716 Aug 7 1991 initoracle.ora
-rw------- 1 oracle 5244928 Mar 9 11:24 lisa_space
-rw------- 1 oracle 1049088 Mar 9 11:24 redo_log1
-rw------- 1 oracle 1049088 Mar 9 13:32 redo_log2
-rw------- 1 oracle 1652 Aug 7 1991 sgadeforacle.dbf
-rw------- 1 oracle 41945088 Mar 9 13:33 system_tablespace
-rw------- 1 oracle 5244928 Aug 7 1991 tempsegs

My guess is that we have no more than about 20 Mb of "raw data". Is there a way to determine this raw size exactly? Assuming the 20 Mb figure is about right, is the extra 74 Mb a reasonable overhead to expect for tables and indexes etc?

Many thanks for any suggestions you may have.
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R. Patrick Goebel                 E-MAIL: patrick_at_casbs.Stanford.EDU
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