I have this select statement, but it never ends:
select * from table where substr(field,1,3)='001'
but when I change it to:
select * from table where left(field,3)='001'
it works! thus, I think it's a resources issue. Now, I'll have to modify the statement but I want to know if it's possible to solve this problem making changes to the db parameters, maybe from:
db2 get db cfg ...
Aditional info:
Version database is 9.5 (windows).
Field is one of 3 key fields of the table.
Table content: 863820 rows
In a comment you ask "I was wondering if it's posible to change a db parameter to allow more resources available to run the first statement "
You could try autoconfigure https://www.ibm.com/support/knowledgecenter/en/SSEPGG_9.5.0/com.ibm.db2.luw.admin.cmd.doc/doc/r0008960.html
e.g. db2 autoconfigure using mem_percent 80 apply none
to see what it would suggest (or change if you say APPLY DB AND DBM and not APPLY NONE) if you asked Db2 to use 80% of your system memory
Related
I have some queries against a Sybase database that after some changes in our Java (JDBC) code are failing to execute because the database is returning an error message where it demands we provide the owner in front of the table name but that is something I would prefer to provide in a single place in our configuration. We are using ASE 16.
For example, we had a query like "SELECT * FROM table_name" that will not work anymore unless we specify "SELECT * FROM database_name..table_name"
I think there should be a simple answer for this but I am struggling to find one, thank you in advance.
We have a legacy application we cannot modify that connects to Oracle 11g and at some point runs a query and returns a result. The application however is using the "generated" column name from Oracle to read the result.
Consider the following query:
select nvl(1,0.0) from DUAL;
As this query does not specify an alias, the generated column name would be "nvl(1,0.0)"
However on another server the generated column name is "nvl(1,0)" (notice 0 and not 0.0) and the application fails.
Is there a configuration that can be changed for Oracle? I've searched for formatting and locale configurations and they are equal on both servers.
Any help would be appreciated
It turns out there's a parameter called cursor_sharing that was set to FORCE instead of EXACT
select nvl(1,0.0) from DUAL;
The query above returns the following depending on the value of the parameter:
FORCE=NVL(1,0)
EXACT=NVL(1,0.0)
I am new to Pentaho data integration tool.I am trying to move data from a source table into target table ... both is SQL Server. The tables are identical and has an identity column.
Tried many options but ... it gives an error every time saying "Indentity insert is set to OFF"
Tried introducing a hop inbetween to execute a SQL statement to "SET identity_insert tblname ON" .. still dint work.
Any suggestions would be highly appreciated.
Thanks.
Putting that in a hop certainly wont work, because PDI/kettle uses a connection(s) per step. You need to put that setting in the advanced options of the database connection and then you should be ok - it will then be used for all instances of that database connection.
Also make sure you "share" your database connections, otherwise if you create them from hand in every transformation you'll need to apply that setting to every single database connection in each transformation. ( Unless you're using a database or EE repository in which case the connections are centralised so you're ok )
One other thing you can try is to remove the identity columns from the select you are using to pass from the source to the destination.
This way, you will make sure that SQL will create a new identity for each one of the rows intead of trying to insert them,
You should add a command after db connection established.
I have the linked server set up in SQL Server 2008. But I could not run any query against the linked server.
I tried to run this simple command but it's not working
SELECT * FROM MYSERVER..ALANH.TEMP_UPDATE1
This is the error I got when I run the above command.
Msg 7399, Level 16, State 1, Line 1
The OLE DB provider "OraOLEDB.Oracle" for linked server "MYSERVER" reported an error. The provider did not give any information about the error.
Msg 7312, Level 16, State 1, Line 1
Invalid use of schema or catalog for OLE DB provider "OraOLEDB.Oracle" for linked server "MYSERVER". A four-part name was supplied, but the provider does not expose the necessary interfaces to use a catalog or schema.
Could anyone help me to connect to the OracleLinkedServer? Thanks very much.
you can be that way too:
**SELECT * FROM OPENQUERY(MYSERVER, 'SELECT * FROM ALANH.TEMP_UPDATE1')**
You can write the query like this:
select * FROM [MYSERVER]..[ALANH].[TEMP_UPDATE1]
Important: In this case, the fully qualified table name must be written in upper case.
You might try the fix from this article.
Also, this could be a problem with naming. From an MS KB article
If you receive these error messages, a table may be missing in the
Oracle schema or you may not have permissions on that table. Verify
that the schema name has been typed by using uppercase. The
alphabetical case of the table and of the columns should be as
specified in the Oracle system tables.
On the Oracle side, a table or a column that is created without double
quotation marks is stored in uppercase. If the table or the column is
enclosed in double quotation marks, the table or the column is stored
as is.
First make sure the tnsping utility works from client server, then use the below string in linked server database source setup
host[:port]/service_name
Check this link for more details :
http://www.oracledistilled.com/oracle-database/oracle-net/using-easy-connect-ezconnect-naming-method-to-connect-to-oracle-databases/
Try something like this:
SELECT * FROM ALL_TABLES#"SOME.SERVER.NAME";
In this case I'm selecting ALL_TABLES from a linked server called SOME.SERVER.NAME.
Richard's post above was critical.
I am using v12 ODP.NET odbc drivers and had to ensure that "Zero Level Only" was NOT checked and that the names supplied for table and schema were the correct case. All of the schemas and tables I access are uppercase only.
Use the query below to determine what the correct table name is, though you will have to supply the schema name in the correct case for the query to work. Try all uppercase, try all lowercase, try mixed case, or better yet get the actual name from the dba (I've heard that only table/schema names that are "" quoted will be allowed mixed case, otherwise in oracle it's all uppercase.)
sp_tables_ex #table_server=InsertLinkedServerHere, #table_schema=InsertSchemaNameHere
Can I find out when the last INSERT, UPDATE or DELETE statement was performed on a table in an Oracle database and if so, how?
A little background: The Oracle version is 10g. I have a batch application that runs regularly, reads data from a single Oracle table and writes it into a file. I would like to skip this if the data hasn't changed since the last time the job ran.
The application is written in C++ and communicates with Oracle via OCI. It logs into Oracle with a "normal" user, so I can't use any special admin stuff.
Edit: Okay, "Special Admin Stuff" wasn't exactly a good description. What I mean is: I can't do anything besides SELECTing from tables and calling stored procedures. Changing anything about the database itself (like adding triggers), is sadly not an option if want to get it done before 2010.
I'm really late to this party but here's how I did it:
SELECT SCN_TO_TIMESTAMP(MAX(ora_rowscn)) from myTable;
It's close enough for my purposes.
Since you are on 10g, you could potentially use the ORA_ROWSCN pseudocolumn. That gives you an upper bound of the last SCN (system change number) that caused a change in the row. Since this is an increasing sequence, you could store off the maximum ORA_ROWSCN that you've seen and then look only for data with an SCN greater than that.
By default, ORA_ROWSCN is actually maintained at the block level, so a change to any row in a block will change the ORA_ROWSCN for all rows in the block. This is probably quite sufficient if the intention is to minimize the number of rows you process multiple times with no changes if we're talking about "normal" data access patterns. You can rebuild the table with ROWDEPENDENCIES which will cause the ORA_ROWSCN to be tracked at the row level, which gives you more granular information but requires a one-time effort to rebuild the table.
Another option would be to configure something like Change Data Capture (CDC) and to make your OCI application a subscriber to changes to the table, but that also requires a one-time effort to configure CDC.
Ask your DBA about auditing. He can start an audit with a simple command like :
AUDIT INSERT ON user.table
Then you can query the table USER_AUDIT_OBJECT to determine if there has been an insert on your table since the last export.
google for Oracle auditing for more info...
SELECT * FROM all_tab_modifications;
Could you run a checksum of some sort on the result and store that locally? Then when your application queries the database, you can compare its checksum and determine if you should import it?
It looks like you may be able to use the ORA_HASH function to accomplish this.
Update: Another good resource: 10g’s ORA_HASH function to determine if two Oracle tables’ data are equal
Oracle can watch tables for changes and when a change occurs can execute a callback function in PL/SQL or OCI. The callback gets an object that's a collection of tables which changed, and that has a collection of rowid which changed, and the type of action, Ins, upd, del.
So you don't even go to the table, you sit and wait to be called. You'll only go if there are changes to write.
It's called Database Change Notification. It's much simpler than CDC as Justin mentioned, but both require some fancy admin stuff. The good part is that neither of these require changes to the APPLICATION.
The caveat is that CDC is fine for high volume tables, DCN is not.
If the auditing is enabled on the server, just simply use
SELECT *
FROM ALL_TAB_MODIFICATIONS
WHERE TABLE_NAME IN ()
You would need to add a trigger on insert, update, delete that sets a value in another table to sysdate.
When you run application, it would read the value and save it somewhere so that the next time it is run it has a reference to compare.
Would you consider that "Special Admin Stuff"?
It would be better to describe what you're actually doing so you get clearer answers.
How long does the batch process take to write the file? It may be easiest to let it go ahead and then compare the file against a copy of the file from the previous run to see if they are identical.
If any one is still looking for an answer they can use Oracle Database Change Notification feature coming with Oracle 10g. It requires CHANGE NOTIFICATION system privilege. You can register listeners when to trigger a notification back to the application.
Please use the below statement
select * from all_objects ao where ao.OBJECT_TYPE = 'TABLE' and ao.OWNER = 'YOUR_SCHEMA_NAME'