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What are some methods for optimizing Oracle databases for large data inserts?

 For large data inserts I can suggest you few things like: Use trigger(PL/SQL) Use APPEND hint Remove indexes on tables Firstly, while you use triggers in the table it could leave data to be logically corrupt. And it will then perform insert in a very conventional way. Which is a time consuming process and won’t helps us! Secondly, using APPEND hint will help us to an extend. So, APPEND hint tells the optimizer to perform a direct-insert into the table, which improves the performance. Now there is a way which we could achieve this by minimizing the Redo generation. What Redo do is; it basically ensures the recoverability of data to the database. It writes down every transaction to the archive log. Let’s take a scenario, where if the database is running on the NOARCHIVELOG mode, using APPEND hint will reduce the redo generation i.e; it won’t write into the archive log anymore and thus increases the speed. But then it won’t be able to recover at any point in time if your data is ambiguou

What are the benefits and drawbacks of having indexes on temporary tables in MySQL?

Indexes are used to retrieve data from the database in a very efficient and fast way. Here are the advantages and disadvantages of index on tables; Click on the link to know more:   Click here

Introduction to SQL

 Q.)  What is SQL ? Ans.) SQL(Structured Query Language) is a standardized language to communicate with the database.  With the help of it we can retrieve data from the database. SQL not only allows us to read the data but also allows us to write the data in the database.  Data in the database is stored in the form of tables. We can Select, Insert, Update, Delete, Create, Alter, Drop and can perform many more operations on the table. And these are called as SQL Statements. * SQL Statements are classified mainly into 4 categories :- 1) DML (Data Manipulation Language) 2) DDL (Data Definition Language) 3) DCL (Data Control Language) 4) TCL (Transaction Control Language) * Under DML we have :-(No Autocommit) 1. Select  2. Insert  3. Update  4. Delete  5. Merge    * Under DDL :-(Allows Autocommit) 1. Create 2. Alter  3. Drop  4. Truncate  5. Flashback * Under DCL :-(Allows Autocommit) 1. Grant  2. Revoke  * Under TCL :-(No Autocommit) 1. Commit 2. Rollback 3. Save point From above, we ca