Oracle Financial Services Software Applications Engineer Interview Questions, Process, and Tips

EXIST checks for the existence of a value in a subquery, while IN checks for the existence of a value in a list.

• EXIST is used with a subquery, while IN is used with a list of values.

• EXIST returns true if the subquery returns any rows, while IN returns true if the value is found in the list.

• EXIST is more efficient for large datasets, while IN is more efficient for small datasets.

• Example: SELECT * FROM table1 WHERE colum...read more

INDEX and PARTITION are database optimization techniques that improve query performance.

• INDEX is a data structure that improves the speed of data retrieval operations on a database table.

• PARTITION is a technique that divides a large table into smaller, more manageable parts.

• INDEX and PARTITION can be used together to further improve query performance.

• Examples of INDEX include B-tree, hash, and bitmap indexes.

• Examples o...read more

Removing duplicates using analytical functions in SQL

• Use the ROW_NUMBER() function to assign a unique number to each row

• Partition the data by the columns that define duplicates

• Order the data by the same columns

• Filter out rows with a row number greater than 1

Oracle DB Architecture is a multi-layered design consisting of physical, logical, and memory structures.

• Physical layer includes data files, redo logs, and control files

• Logical layer includes tablespaces, schema objects, and segments

• Memory structures include SGA and PGA

• Oracle uses a client-server architecture with a listener process

• Oracle also supports RAC (Real Application Clusters) for high availability and scalabilit

ANSI JOINS are standard SQL joins while Oracle JOINS are specific to Oracle database.

• ANSI JOINS are supported by most relational databases while Oracle JOINS are specific to Oracle.

• ANSI JOINS use keywords like INNER JOIN, LEFT JOIN, RIGHT JOIN, etc. while Oracle JOINS use symbols like (+) for outer joins.

• ANSI JOINS are more portable and easier to migrate to other databases while Oracle JOINS are more efficient in Oracl...read more