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Updated: 3 hours 9 min ago

PL/SQL-Collections: EXISTS for Associative Array

Fri, 11/28/2014 - 00:00
Hi Tom, In the Documentation is written that: "You cannot use EXISTS if collection is an associative array" But I have tried this and it works very fine. Please check this Siite which uses an associative array indexed by varchar2: http://...

Minimum of a Date column

Fri, 11/28/2014 - 00:00
Hello Tom, I am working on a current project wherein the requirement to calculate a certain column in a certain table is as under. The base table is this: <code> create table main_data (from_value varchar2(10), to_value varchar2(10), act...

Not really a tech question

Thu, 11/27/2014 - 00:00
Not really a technically question. Just wanted to know, where have you been. There was no activity on asktom for some months now.

How to Find Min/Max Dates for Data Having Constant Value

Thu, 11/27/2014 - 00:00
In the example below, how can I create a query to give me the results shown, such that for any sequence of consecutive rows, ordered by date, which have the same value for N, I can find the date values at the beginning and end of the range? I have a...

your 2 new books

Thu, 11/27/2014 - 00:00
Hello Tom, You have recently published 2 new books with D. Kuhn: - Expert Oracle Database Architecture 3rd edition - Oracle Database Transactions and Locking Revealed. The 2nd book looks like a kind of subset of the first book: could you conf...

Views Efficiency

Thu, 11/27/2014 - 00:00
Tom, Glad to be able to post a question. Thank you. My questions is How can I improve the efficiency of the following view. This will help not only on this view but similar likes ones throughout the application. Any points will be appreciated. t ...

Starting a PL_SQL_Procedure paralell

Thu, 11/27/2014 - 00:00
Hi Tom, I have a Procedure which distributes data from 3 Tables to other tables. Therefore the procedure fetches every single row from the 3 tables (checks if the data of the 3 rows are ok). Then the date are inserted, updated into other tables....

Select range of strings between two other strings

Wed, 11/26/2014 - 00:00
Hi, Tom. I need to create a bulk of serial numbers in one of my tables and for that I want to create a stored procedure. I want to pass first SN and last SN and the procedure to return all the SN in between these two. How can I do that without usin...

Exporting pivot query resultset into excel sheet

Tue, 11/25/2014 - 00:00
Hi, Greetings! Requirement : Extract and transpose data from a table and export it into an excel sheet. I am trying to transpose the data using Pivot. Since the number of columns and rows will vary, therefore I have created the query dynamic...


Tue, 11/25/2014 - 00:00
Index on standard table affect the performance ? If not why oracle is not supporting for the custom index?

SQL Plan Baselines questions

Tue, 11/25/2014 - 00:00
Tom, We have an application(situation), where one of the query is performing poor which is written without analytics, when used analytics it was far better. we dont have time to make this code change right now immediately, so thought of using SPM...

Oracle database In Memory

Tue, 11/25/2014 - 00:00
Hello Tom, I seen a new feature for Oracle 12c : In-Memory database cache. I seen it's a new memory area to organize data in column format for BI/DWH queries. I would like to know how Oracle decides when use the data from In-memory area or from...

Number of Connections per GUI

Tue, 11/25/2014 - 00:00
Tom, we are a small software company that has developed a customer-facing Graphical User Interface (GUI) that connects to a customer-hosted Oracle 11g database. This is a two-tier, classic client/server setup. The GUI uses Oracle Data Provider (ODP...

Linguistic Indexes

Tue, 11/25/2014 - 00:00
Tom, Can you explain what is the need for the "Table access by rowid" here? why dont the index act like skinny version of table here? <code> rajesh@ORA11G> create table t 2 as 3 select a.*, object_name x 4 from all_objects a; Tab...

How to get FULL Result Set in a Variable

Tue, 11/25/2014 - 00:00
Hello Tom, We are developing an application internally, for which I am using Oracle PL-SQL. As part of a specific function, I am trying to execute a SELECT * command using PL-SQL, store the output of this command in a variable, and display it. ...


Tue, 11/25/2014 - 00:00
Tom: I am practising "Set DB_FILE_MULTIBLOCK_READ_COUNT to Reduce Full-Scan Costs" from Effective Oracle by design in Oracle 10g database. I am aware that things changes over the version of oracle. q1 - below is what i got from Trace file in 1...


Tue, 11/25/2014 - 00:00
Tom, I was trying to tune one of the sql written in Ansi syntax without toughing using dbms_advanced_rewrite API. but ended up with the below error, Can you help me what i am missing here? <code> rajesh@ORA10G> declare 2 l_src long; ...

Indexes Maintenance in a Managed Hosting Setup

Mon, 11/24/2014 - 00:00
Hi Tom, We have a Oracle Standard Edition installed in a managed hosting environment. The various clients access data pertinent to them using CLIENT_ID column added to each table ( when a client issues "SELECT * FROM MYTAB", it actually becomes...