Oracle shared pools contains two layers:

1. library cache
2. data dictionary cache

Save points are used to divide a transaction into smaller parts. It allows rolling back of a transaction. Maximum five save points are allowed. It is used to save our data, whenever you encounter an error you can roll back from the point where you save your SAVEPOINT.

Hash cluster is a technique to store a data in hash table and improve the performance of data retrieval. Hash function is applied on table row's cluster key value and store in hash cluster.

Tables: This is a set of elements organized in vertical and horizontal fashion.

Tablespaces: This is a logical storage unit in Oracle.

Views: It is virtual table derived from one or more tables.

Indexes: This is a performance tuning method to process the records.

Synonyms: This is a name for tables.

A pre-query trigger fire before the query executes and fire once while you try to query. With the help of this trigger you can modify the where clause part dynamically.

Pre-select query fires during the execute query and count query processing after Oracle forms construct the select statement to be issued, but before the statement is actually issued.

Pre-query trigger fires before Pre-select trigger.

Following are the different modules in Oracle forms:

• Form module
• Menu module
• Pl/SQL Library module
• Object Library module

ANALYZE command is used to perform various functions on index, table, or cluster. The following list specifies the usage of ANALYZE command in Oracle:

• It is used to identify migrated and chained rows of the table or cluster.
• It is used to validate the structure of the object.
• It helps in collecting the statistics about object used by the optimizer. They are then stored in the data dictionary.
• It helps in deleting statistics used by object from the data dictionary.

Yes. We can create a synonym without having a base table.

• Self join
• Outer Join
• Equi-join

In Oracle, control file is used for database recovery. The control file is also used to identify the database and redo log files that must be opened for database operation to go ahead, whenever an instance of an ORACLE database begins.