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Relational vs Document Databases
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Relational vs Document Databases

EasySQL · PostgreSQL

Problem

What is RDBMS, and explain the types of joins in SQL

Asked in the Technical stage. Provide a concise explanation of RDBMS and the common SQL join types, then write a PostgreSQL query using the Newgen OmniDocs sample tables.

Output

  1. One row per document, including documents without an assigned owner
  2. Columns: document_id, document_title, owner_name, and assignment_status
  3. Sort by document_id ascending, with unassigned documents included

Schema

omnidocs_documents
ColumnTypeDescription
document_idPKINTUnique document identifier
document_titleVARCHAR(150)Document title
owner_idINTOptional reference to the document owner
omnidocs_users
ColumnTypeDescription
owner_idPKINTUnique owner identifier
owner_nameVARCHAR(100)Owner display name
Tablesomnidocs_documentsomnidocs_users
Interviewer

Your question is Relational vs Document Databases. Start with the requirements and the two tables in the Question tab.

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