Question:- What is the sequence?
Answer:- For numerical columns in database tables, a sequence produces a serial list of unique numbers. For data where we want to insert data in a systematic way, we may use the sequence on columns.
Question:- What is the definition of the table in Oracle?
Answer:- In a database, the table is the first physical object. Oracle divides data into rows and columns using tables in a database. In a database, the table is the first physical object.
Question:- What do you mean by a view in SQL terminology?
Answer:- A query is added to any view in order to define specific rows and columns of the table. The view is a type of virtual table. Read-only and read-write views are available types of views.
Question:- Explain the advantages of using view?
Answer:- The advantages of using a view in the table are • It is a subset of the data in table • It store complex queries • It can simplify multiple tables into one • It occupies very little space • It presents the data from different perspectives
Question:- In Oracle terminology, what do you mean by tablespace?
Answer:- A tablespace is a logical storage unit that groups together similar logical structures. It is the logical structure that will organise all of the database’s objects.
Question:- How long does it take for the SYSTEM tablespace to be created?
Answer:- Every database in Oracle has a tablespace called SYSTEM, which is generated automatically when the database is created. It also includes a data dictionary table for the entire set of data.
Question:- What is the relationship between tablespace and datafiles?
Answer:- Each database has one or more tablespaces, each of which is divided into one or more data files.
Question:- How do we use the materialized view?
Answer:- Materialized views are items that contain condensed sets of data from base tables that have been summarised, clustered, or aggregated. They’re commonly used in data centres and decision-making systems.
Question:- What is the use of the SELECT statement?
Answer:- The SELECT statement is used to retrieve a collection of unique values from a database table based on the conditions defined in a SQL query.
Question:- How can you compare a part of the name rather than the entire name?
Answer:- To compare different parts, we use the LIKE operator, which functions as a database’s regex engine.
Question:- What is the keyword to get distinct records from a table?
Answer:- The user will use SELECT DISTINCT to select distinct values from a database table.
Question:- In order to get sorted records from a table, what is the keyword?
Answer:- The keyword ORDER BY is used to sort the data.. It returns the sorted results to your program.
Question:- In order to get total records from a table, what is the keyword?
Answer:- The COUNT keyword is used to find the total number of records in a table.
Question:- What is the definition of GROUP BY?
Answer:- The keyword GROUP BY is an aggregate function like SUM, MULTIPLE, and so on, and without it, the sum for each individual group value cannot be determined.