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T1

a INT	b INT
0	1
2	3

T2

| a INT | b INT | c INT |

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SELECT 
  a, c
FROM
  T1, T2;

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SELECT 
  InnerResult.T1.a 
FROM 
  (SELECT 
    T1.a, c 
   FROM 
    T1, T2) AS InnerResult 
WHERE
  InnerResult.T1.a = InnerResult.c;

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SELECT 
  InnerResult.a 
FROM 
  (SELECT 
      T1.a, c 
   FROM 
      T1 JOIN T2 ON InnerResult.a = InnerResult.c
  ) AS InnerResult;

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SELECT 
  InnerResult[0] 
FROM 
  (SELECT 
     T1[0], T2[2] 
   FROM 
     T1 JOIN T2 ON T1[0] = T2[2]
) AS InnerResult;

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SELECT * FROM a, b WHERE a.id = b.id;

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SELECT * FROM a INNER JOIN b ON a.id = b.id;

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SELECT c_balance, c_first, c_middle, c_id
FROM customer
WHERE c_last=? AND c_d_id=? AND c_w_id=?
ORDER BY c_first;

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  auto gt_customer = std::make_shared<opossum::GetTable>("CUSTOMER");
  auto validate = std::make_shared<opossum::Validate>(gt_customer);

  auto first_filter = std::make_shared<opossum::TableScan>(validate, opossum::ColumnID{5} /* "C_LAST" */,
                                                           opossum::ScanType::OpEquals, c_last);

  auto second_filter = std::make_shared<opossum::TableScan>(first_filter, opossum::ColumnID{1} /* "C_D_ID" */,
                                                            opossum::ScanType::OpEquals, c_d_id);

  auto third_filter = std::make_shared<opossum::TableScan>(second_filter, opossum::ColumnID{2} /* "C_W_ID" */,

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-- In the inner query
 --   * c needs to be resolved to ”T2”, but could also be referred by ”T2.c”
--    * T1.a needs to have the prefix, because ”T2” also contains a column ”a”
 --   * The first output column is nevertheless named “a” and not “T1.a”
 -- In the outer query, the ”InnerResult” prefix is, again, optional, but 
--   the subquery needs to have an alias
SELECT 
  InnerResult.a 
FROM 
  (SELECT