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Data Loading [Sqlldr Direct Path] Part -2

SQL*Loader with different loading options: SQL*Loader have to methods for loading data as mention below:  Conventional path Direct path But we normally use conventional path in our  daily life, Direct path load is a very good option oracle provides to increase loading performance. Pre-requisite: The target table where this utility will load data that must be there at targeted schema, As SQL* loader never create tables it only help to load data in existing table. And also the user for which you are executing this process he have to have INSERT and DELETE privileged. So in conventional way once we execute sqlldr command it internally process sql commands[Insert with bind varray buffer] to load it and for that it start searching for those blocks which are with in HWM means search for partial fill blocks or those blocks which are still vacant due to delete activity, Moral is it does not increase HWM instead it will search unused block with in HWM. And due to this activit

Data Loading in Oracle

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Data loading concept In our daily life we face such situation where we have to load a huge number of data into our oracle db,We do face lots of issue during those operations and also performance related issues as well. I am trying to address some of those issues as well as trying to give some description about few utility how they works. Some available techniques are as follows:  External table Sqlldr Utl_file Insert APPEN Note: INSERT APPEND supports only the subquery syntax of the INSERT statement, not the VALUES clause Partition exchange Bulk loading using forall Oracle Data Pump Export Import Question is which one is better performer in above mentioned list. Please find a diagram below relented to their performance. So this chart representing that SQLLDR is one of the best way to load data with maximum performance. SQL loader SQL*Loader () is the utility to use for high performance data loads. The data can be loaded from any text file a

Oracle Interview Questions-Part-1 [Basic questions]

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Some basic useful Oracle Interview Questions-Part-1 DDL Data Definition Language (DDL) statements are used to define the database structure or schema. Some examples: CREATE - to create objects in the database ALTER - alters the structure of the database DROP - delete objects from the database TRUNCATE - remove all records from a table, including all spaces allocated for the records are removed COMMENT - add comments to the data dictionary RENAME - rename an object DML   Data Manipulation Language (DML) statements are used for managing data within schema objects. Some examples: SELECT - retrieve data from the a database INSERT - insert data into a table UPDATE - updates existing data within a table DELETE - deletes all records from a table, the space for the records remain MERGE - UPSERT operation (insert or update