Jodbc works with LOB columns?

Hi,
I would like to now if the jodbc drivers (thin and/or OCI) work
with LOB columns.
Browsing the generic Server 804 docs in Oracle Technet site, I
read that jodbc thin drivers don't, but that the OCI drivers do.
But the jodbc.htm that camne with the 8.0.5 production release
for Linux doesn't mention LOB columns, only LONG and LONG RAW.
Was it just an oversight in the Oracle2Linux doc, or the jodbc
OCI driver for Linux really doesn work with LOBs? (or is the
generic docs wrong and none of the OCI driver work with LOBs?)
Anybody knows?
Any info would be greatly apreciated.
Leandro
null

The amount of data is not really material, in this type of decision, it is the way you would most often access the data that is important. If the lobs are larger than about 4K they will be stored out of line (in a separate table) anyway, with only lob pointers in the actual table. You could look at partitioning (probably a hash partition would work best) to deal with the amount of data.
If you mostly query for a single attribute (i.e. You access a persons photo hundreds of times a day, but only look for a finger print once or twice a day), then it may make sense to split the table into three.
However, if you most often need to pull all three attributes, then storing in a single table makes most sense. Particularly since you say you do not always have all three attributes for a given person. With three tables, you will always be outer joining.
HTH
John

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at Oracle.DataAccess.Client.OracleBulkCopy.WriteDataSourceToServer()
at Oracle.DataAccess.Client.OracleBulkCopy.WriteToServer(IDataReader reader)
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I'm using Oracle 11gR2.
Has anyone seen this or have an idea how to solve it?
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From the doc:
Data Types Supported by Bulk Copy
The data types supported by Bulk Copy are:
ORA_SB4
ORA_VARNUM
ORA_FLOAT
ORA_CHARN
ORA_RAW
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Only the Sql Dev team can respond to that question.
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Oracle 11.2 - Perform parallel DML on a non partitioned table with LOB column

Hi,
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Parallel execution of the following DML operations on tables with LOB columns is supported. These operations run in parallel execution mode only when performed on a partitioned table. DML statements on non-partitioned tables with LOB columns continue to execute in serial execution mode.
INSERT AS SELECT
CREATE TABLE AS SELECT
DELETE
UPDATE
MERGE (conditional UPDATE and INSERT)
Multi-table INSERT
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SQL> CREATE TABLE T1 (A BLOB);
Table created.
Then, I tried to see the execution plan of a parallel DELETE:
SQL> EXPLAIN PLAN FOR
2 delete /*+parallel (t1,8) */ from t1;
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 3718066193
| Id | Operation             | Name     | Rows | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | DELETE STATEMENT      |          | 2048 |     2   (0)| 00:00:01 |        |      |            |
|   1 | DELETE               | T1       |       |            |          |        |      |            |
|   2 |   PX COORDINATOR      |          |       |            |          |        |      |            |
|   3 |    PX SEND QC (RANDOM)| :TQ10000 | 2048 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   4 |     PX BLOCK ITERATOR |          | 2048 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
|   5 |      TABLE ACCESS FULL| T1       | 2048 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
PLAN_TABLE_OUTPUT
Note
   - dynamic sampling used for this statement (level=2)
And I finished by executing the statement.
SQL> commit;
Commit complete.
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Session altered.
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2048 rows deleted.
As we can see, the statement has been run as parallel:
SQL> select * from v$pq_sesstat;
STATISTIC                      LAST_QUERY SESSION_TOTAL
Queries Parallelized                    1             1
DML Parallelized                        0             0
DDL Parallelized                        0             0
DFO Trees                               1             1
Server Threads                          5             0
Allocation Height                       5             0
Allocation Width                        1             0
Local Msgs Sent                        55            55
Distr Msgs Sent                         0             0
Local Msgs Recv'd                      55            55
Distr Msgs Recv'd                       0             0
11 rows selected.
Is it normal ? It is not supposed to be supported on Oracle 11g with non-partitioned table containing LOB column....
Thank you for your help.
Michael

Yes I did it. I tried with force parallel dml, and that is the results on my 12c DB, with the non partitionned and SecureFiles LOB column.
SQL> explain plan for delete from t1;
Explained.
| Id | Operation             | Name     | Rows | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | DELETE STATEMENT      |          |     4 |     2   (0)| 00:00:01 |        |      |            |
|   1 | DELETE               | T1       |       |            |          |        |      |            |
|   2 |   PX COORDINATOR      |          |       |            |          |        |      |            |
|   3 |    PX SEND QC (RANDOM)| :TQ10000 |     4 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   4 |     PX BLOCK ITERATOR |          |     4 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
|   5 |      TABLE ACCESS FULL| T1       |     4 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
The DELETE is not performed in Parallel.
I tried with another statement :
SQL> explain plan for
2        insert into t1 select * from t1;
Here are the results:
11g
| Id | Operation                | Name     | Rows | Bytes | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | INSERT STATEMENT         |          |     4 | 8008 |     2   (0)| 00:00:01 |        |      |            |
|   1 | LOAD TABLE CONVENTIONAL | T1       |       |       |            |          |        |      |            |
|   2 |   PX COORDINATOR         |          |       |       |            |          |        |      |            |
|   3 |    PX SEND QC (RANDOM)   | :TQ10000 |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   4 |     PX BLOCK ITERATOR    |          |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
|   5 |      TABLE ACCESS FULL   | T1       |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
12c
| Id | Operation                          | Name     | Rows | Bytes | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | INSERT STATEMENT                   |          |     4 | 8008 |     2   (0)| 00:00:01 |        |      |            |
|   1 | PX COORDINATOR                    |          |       |       |            |          |        |      |            |
|   2 |   PX SEND QC (RANDOM)              | :TQ10000 |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   3 |    LOAD AS SELECT                  | T1       |       |       |            |          | Q1,00 | PCWP |            |
|   4 |     OPTIMIZER STATISTICS GATHERING |          |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
|   5 |      PX BLOCK ITERATOR             |          |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
It seems that the DELETE statement has problems but not the INSERT AS SELECT !

ASSM and table with LOB column

I have a tablespace created with ASSM option. I've heard about that tables with LOB columns can't take the advantage of ASSM.
I made a test : create a table T with BLOB column in a ASSM tablespace. I succeeded!
Now I have some questions:
1. Since the segments of table T can't use ASSM to manage its blocks, what's the actrual approach? The traditional freelists??
2. Will there be some bad impacts on the usage of the tablespace if table T becomes larger and larger and is used frequently?
Thanks in advance.

Can you explain what you mean by #1 because I believe it is incorrect and it does not make sense in my personal opinion. You can create a table in an ASSM tablespace that has a LOB column from 9iR2 on I believe (could be wrong). LOBs don't follow the traditional PCTFREE/PCTUSED scenario. They allocate data in what are called "chunks" that you can define at the time you create the table. In fact I think the new SECUREFILE LOBs actually require ASSM tablespaces.
HTH!

Export table with LOB column

Hi!
I have to export table with lob column (3 GB is the size of lob segment) and then drop that lob column from table. Table has about 350k rows.
(I was thinking) - I have to:
1. create new tablespace
2. create copy of my table with CTAS in new tablespace
3. alter new table to be NOLOGGING
4. insert all rows from original table with APPEND hint
5. export copy of table using transport tablespace feature
6. drop newly created tablespace
7. drop lob column and rebuild original table
DB is Oracle 9.2.0.6.0.
UNDO tablespace limited on 2GB with retention 10800 secs.
When I tried to insert rows to new table with /*+append*/ hint operation was very very slow so I canceled it.
How much time should I expect for this operation to complete?
Is my UNDO sufficient enough to avoid snapshot too old?
What do you think?
Thanks for your answers!
Regards,
Marko Sutic

I've seen that document before I posted this question.
Still I don't know what should I do. Look at this document - Doc ID: 281461.1
From that document:
FIX
Although the performance of the export cannot be improved directly, possible
alternative solutions are:
+1. If not required, do not use LOB columns.+
or:
+2. Use Transport Tablespace export instead of full/user/table level export.+
or:
+3. Upgrade to Oracle10g and use Export DataPump and Import DataPump.+
I just have to speed up CTAS little more somehow (maybe using parallel processing).
Anyway thanks for suggestion.
Regards,
Marko

Table with LOB column

Hi,
I have a proble. How to move a table with LOB colum? How to create a table with LOB column by specifying another tablespace for LOB column?
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Regards,
Mathew

What is it that you are not able to find?
The link that I provided was answer to your second question.

Membership rules does not work with UDF column name having the max length

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Steps to Reproduce
1.Create a UDF having max column name length for eg UDF_USR_PERSONAL_SUB_DOMAIN_CO (lable = Personal Code)
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3. Assign this Rule as a member ship rule of a Group.
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Thanks
Suren

Yes , i verified logs as well .
If you just decrease the column name length , w/o making change to any other attributes , it starts working ..
Thanks
Suren

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UPDATE some_table
SET some_column = 4
WHERE ROWID = <<ROWID A>>updates the correct row.
Justin

How can I work with report columns in computation or validation?

Hi all,
I have an updateable report. Bevor submitting canges, I want to do computation or validation on one of the report columns. But a report column is not an item. Is there a possibility to work with report colums?
Thanks, Daniela

Hi Daniela,
Presumably, your tabular form has been created using the wizard?
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When you have time, you should have a look at the HTMLDB_ITEM package api documentation as this explains how you can manually construct a tabular form. But for now, for the "display only" column, you need to do something like:
select
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FROM table
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Hi,
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Hi,
I have been unable to make any progress on this issue. I have made use of prebuilt update handlers with no problems
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which I hope make sense and are relevant:
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4.Finally, if I need to resolve in favour of the LCR, do I need to call something specific for LOB related columns compared to non-LOB columns?
Any help with these would be very much appreciated or even if someone can direct me to documentation or other links that would be good too.
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Add columns to a table with lob column

Hi,
Just a quick question: is there a performance penalty after adding columns to a table with a lob fied? the lob field is now the last column in the table and via via I was told that adding columns will impact badly the IO performance on the table if the lob field isn't anymore the last column. The table is on a Oracle 10.2.0.3 version.
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I have generated a jTable on runtime. I have created an object of DefaultTableModel and used it to create the jTable.
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new Object[][]{},
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java.lang.Boolean.class, java.lang.Object.class
boolean[] canEdit = new boolean [] {
true, false
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return types[columnIndex];
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Hi Gurus,
I need to check the exact amount of space used (in bytes or MB) by a table which is having a BLOB column.
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select segment_name , sum(bytes)
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create or replace procedure sp_get_table_size (p_table_name varchar2)
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    l_used_bytes            number;
    l_expired_blocks        number;
    l_expired_bytes         number;
    l_unexpired_blocks      number;
    l_unexpired_bytes       number;
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        segment_size_bytes      => l_segment_size_bytes,
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        used_bytes              => l_used_bytes,
        expired_blocks          => l_expired_blocks,
        expired_bytes           => l_expired_bytes,
        unexpired_blocks        => l_unexpired_blocks,
        unexpired_bytes         => l_unexpired_bytes
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    dbms_output.put_line('used_blocks               => '|| l_used_blocks);
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    dbms_output.put_line('expired_blocks            => '|| l_expired_blocks);
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end sp_get_table_size;
But it is giving the error
Error starting at line 298 in command:
exec sp_get_table_size ('TEST_CLOB_ADV')
Error report:
ORA-03213: Invalid Lob Segment Name for DBMS_SPACE package
ORA-06512: at "SYS.DBMS_SPACE", line 210
ORA-06512: at "SYS.SP_GET_TABLE_SIZE", line 20
ORA-06512: at line 1
03213. 00000 - "Invalid Lob Segment Name for DBMS_SPACE package"
*Cause:    The Lob Segment specified in the DBMS_SPACE operation does not
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*Action:   Fix the Segment Specification
Although the LOB section is specified in create table syntax.
Please help.
Thanks
Amitava.

Here is a query that I use, to associate space from all segments under s schema (LOBs, indexes, etc.) back to the tables they support:
with schema as (select '&your_schema' as name from dual),
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union all
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and Seg.OWNER = i.owner and seg.segment_name = i.index_name
union all
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and seg.OWNER = lob.owner and seg.segment_name = lob.segment_name
union all
select 'LOB' seg_supertype, lob.table_name as related_table, seg.* from dba_segments seg, dba_lobs lob, schema where seg.owner = schema.name and seg.segment_type in ('LOBINDEX')
and seg.OWNER = lob.owner and seg.segment_name = lob.index_name
select owner,related_table,
segment_type,   segment_name , partition_name, blocks
from segs_by_table, schema
where owner = schema.name
--and related_table like 'BLOB_TEST%'
order by owner,related_table, segment_type, segment_name;
You can revise as needed to limit to a single table, to summarize, etc.
Mike

Jodbc works with LOB columns?

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