Cassandra Query Language (CQL)- Shikshaglobe

Content Creator: Satish kumar

Embed Data

The Cassandra embed articulation composes information in Cassandra sections in line structure. Cassandra embed inquiry will store just those sections that are given by the client. You need to determine only the essential key section fundamentally.It won't take any space for not given values. No outcomes are returned after addition.Here is the preview of the executed Cassandra Insert into table question that will embed one record in Cassandra table 'Understudy'.

Embed into order in Cassandra Query Language

Embed into University.Student(RollNo,Name,dept,Semester) values(2,'Michael','CS', 2);After effective execution of the order Insert into Cassandra, one column will be embedded in the Cassandra table Student with RollNo 2, Name Michael, dept CS and Semester 2.Here is the preview of the ongoing data set state.

Upsert Data

Cassandra does upsert. Upsert implies that Cassandra will embed a line on the off chance that an essential key doesn't exist currently in any case assuming essential key as of now exists, it will refresh that column.

Update Data

The Cassandra Update question is utilized to refresh the information in the Cassandra table. On the off chance that no outcomes are returned in the wake of refreshing information, it implies information is effectively refreshed if not a blunder will be returned. Section values are changed in 'Set' provision while information is sifted with 'Where' statement.After effective execution of the update question in Cassandra 'Update Student', understudy name will be changed from 'Clark' to 'Hayden' that has rollno 1.Here is the screen capture that shows the information base state subsequent to refreshing information.Illustration of Update order in Cassandra Query Language

Cassandra Delete Data

Order 'Erase' eliminates a whole line or a few sections from the table Student. At the point when information is erased, it isn't erased from the table right away. Rather erased information is set apart with a gravestone and are eliminated after compaction.After fruitful execution of the CQL Delete order, one columns will be erased from the table Student where rollno esteem is 1.Here is the preview that shows the data set state in the wake of erasing information.Illustration of Delete order in Cassandra Query Language

What Cassandra doesn't uphold

There are following impediments in Cassandra question language (CQL).

CQL doesn't uphold conglomeration inquiries like max, min, avg

CQL doesn't uphold bunch by, having inquiries.

CQL doesn't uphold joins.

CQL doesn't support OR inquiries.

CQL doesn't uphold special case inquiries.

CQL doesn't uphold Union, Intersection questions.

Table segments can't be sifted without making the list.

More prominent than (>) and not exactly (<) inquiry is just upheld on bunching section.

Cassandra inquiry language isn't reasonable for investigation purposes since it has such countless impediments.

Cassandra Where Clause

In Cassandra, information recovery is a delicate issue. The segment is separated in Cassandra by making a list on non-essential key sections.Two records are recovered from Student table.Here is the depiction that shows the information recovery from Student with information filtration. One record is recovered.



Click Here For More Detail:

Hive Create Table 
Hive Partitions & Buckets 
Hive Indexes and View 
Hive Queries 

Featured Universities

Mahatma Gandhi University

Location: Soreng ,Sikkim , India
Approved: UGC
Course Offered: UG and PG

MATS University

Location: Raipur, Chhattisgarh, India
Approved: UGC
Course Offered: UG and PG

Kalinga University

Location: Raipur, Chhattisgarh,India
Approved: UGC
Course Offered: UG and PG

Vinayaka Missions Sikkim University

Location: Gangtok, Sikkim, India
Approved: UGC
Course Offered: UG and PG

Sabarmati University

Location: Ahmedabad, Gujarat, India
Approved: UGC
Course Offered: UG and PG

Arni University

Location: Tanda, Himachal Pradesh, India.
Approved: UGC
Course Offered: UG and PG

Capital University

Location: Jhumri Telaiya Jharkhand,India
Approved: UGC
Course Offered: UG and PG

Glocal University

Location: Saharanpur, UP, India.
Approved: UGC
Course Offered: UG and PG

Himalayan Garhwal University

Location: PG, Uttarakhand, India
Approved: UGC
Course Offered: UG and PG

Sikkim Professional University

Location: Sikkim, India
Approved: UGC
Course Offered: UG and PG

North East Frontier Technical University

Location: Aalo, AP ,India
Approved: UGC
Course Offered: UG and PG