Q: Which low-cost database service supports strong consistency, atomic transaction and serializable isolation?

A columnar database is a type of database management system that stores data in columns rather than rows, which makes it easier for analytical queries.

Memory paging is a memory management technique that stores and retrieves data from secondary storage for use in main memory. By paging, programs in secondary storage can exceed the physical storage capacity, which is a crucial component of virtual memory.

A columnar database refers to a columnar format, a database management system (DBMS) that stores the data within the format. In Google Cloud Platform (GCP), Bigdata is a solution for columnar databases.

To handle null values in data, you can use the following methods:

• Delete or exclude rows with null values
• Replace null values with a default value
• You can use interpolation techniques to fill in missing values

A deadlock in a DBMS (Database Management System) refers to a situation where multiple transactions are stuck and unable to proceed.