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Updated: 12 min 12 sec ago

Converting data types in where clause

Tue, 09/24/2019 - 00:00
Hi Tom, My question is regarding when a query is not having the right datatype in the where clause Example: -- Create table <code>CREATE TABLE mytable ( mynumber varchar2(20), primary key(mynumber));</code> -- Insert some rows <...

Inserting without a full list for field names

Tue, 09/24/2019 - 00:00
We have an issue when we perform an insert like this <code> INSERT INTO STS_RESP_LOG(STS_REQ_LOG_SYSTEM_ID,HSTRY_FLG, SNGL_STS, FRQNCY, CRT_DATE ) VALUES ( ?, ?, ?, ?, sysdate); </code> ?...

confuse at the order of execution plan table

Tue, 09/24/2019 - 00:00
As we were told that "The execution order in EXPLAIN PLAN output begins with the line that is the furthest indented to the right. The next step is the parent of that line. If two lines are indented equally, then the top line is executed first." howe...

md5 vs natural key

Thu, 08/15/2019 - 00:00
Hello, I start a new data warehouse project. In the ETLs for the ins/upd steps, I suggest to use MD5 and not the natural key (my sources are txt files from a mainframe). I need to explain to my project manager why I want to use md5 and not the na...

Generate duplicate rows

Wed, 08/14/2019 - 00:00
Hi Connor / Chris, Could you please have a look ate below scenario and help in building SQL: I need to generate duplicate row based on column value in SELECT SQL to be executed is: <code> select emp.empno, emp.ename, emp.hiredate, emp.sal, e...

Select Performance Too Bad on Oracle

Wed, 08/14/2019 - 00:00
Dear Tom, I just faced an issue that I could not solve it. I have two virtual machines: Client: 32Core, 32G Ram, Virtual Machine on HPE Server Server: 96Core, 256G Ram, Virtual Machine on HPE Server I did write a simple Java application usi...

Truncate Table Command not able to recognize Table in EBR enabled Oracle database

Tue, 08/13/2019 - 00:00
We are using EBR enabled Oracle Database and hence have ability to have same name for a table and View. Following are two objects in FUSION schema: wsh_interface_errors TABLE FUSION WSH_INTERFACE_ERRORS VIEW FUSION Now when trying to run...

Write stored procedure inside a stored procedure

Tue, 08/13/2019 - 00:00
Hi Team Ask TOM, Recently, I came across some code where developers had written four or five stored procedures inside another stored procedure. The code compiles fine. I always thought that to write stored procedures like this, they should be in a p...

Oracle SQL Index Optimization : Index Hint not being used even on forcing

Mon, 08/12/2019 - 00:00
Dear Sir, I have created a table with a composite primary key and few indexes. In one of the SQL the where clause is a combination of Index Column and non-index columns, however the query is not using the index column and instead going for Full Ta...

Script to create dynamic partitions for multiple backup tables

Mon, 08/12/2019 - 00:00
Hi Team, We have a requirement wherein there are 30 backup tables which are currently non partitioned and each table have data around 15-30TB's. Size of the table is very huge. We have to write a script which will create partitioning of a backu...

SQL query using Rollback segment heavily

Thu, 08/08/2019 - 00:00
Dear Team, I am querying from a table where dml operations are continuously taking place in current financial year(19-20). But I am retrieving data of 17-18 financial year's and it was pretty slow. On investigating, I found that it was using rollbac...