Basic SQL Query

• relation-list : A list of relation names

  • possibly with a range-variable after each name

• target-list : A list of attributes of tables in relation-list

• qualification : Comparisons combined using AND, OR and NOT.

  • Comparisons are Attr op const or Attr1 op Attr2, where op is one of

• DISTINCT: optional keyword indicating that the answer should not contain duplicates.

  • Default is that duplicates are not eliminated!

SELECT [DISTINCT] target-list

FROM relation-list

WHERE qualification

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