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DBMS Keys and Normal Forms
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DBMS Keys and Normal Forms

EasySQL · PostgreSQL

Problem

Explain DBMS basics including keys and normal forms.

Use the relation below and answer the question by identifying the correct key properties and normalization level for each row set. Rows with a NULL in candidate_key_value are ignored.

Output

  1. One row per relation_name
  2. Columns: relation_name, candidate_key_value, is_primary_key, is_candidate_key, normal_form
  3. Ignore rows where candidate_key_value is NULL
  4. Sort by relation_name, then candidate_key_value

Schema

dbms_basics
ColumnTypeDescription
relation_nameVARCHAR(100)Name of the relation being evaluated
candidate_key_valueVARCHAR(100)Example value used to discuss key uniqueness
is_primary_keyBOOLEANWhether the value is the chosen primary key
is_candidate_keyBOOLEANWhether the value is a minimal unique identifier
normal_formVARCHAR(20)Highest normal form satisfied by the relation
Tablesdbms_basics
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