Ambigous column name

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Revision as of 11:15, 19 July 2012 by Marek (talk | contribs) (Created page with "<div class='err'> <div class=params>schema:gisq</div> <div class = "link e-oracle>ORA-00918: column ambiguously defined</div> <div class = "link e-mysql>Error 1052 Column 'nam...")
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schema:gisq

Problem

When more than one table is used (in a JOIN for example) there may be two columns with the same name.

In this example there is a column called name

in bbc and also in cia.

Solutions

  • Include the table name before the column name:
    SELECT bbc.name
      FROM bbc JOIN cia ON bbc.name = cia.name
    
  • Alias at least one of the tables and use that
    SELECT B.name
    FROM bbc B JOIN cia ON B.name = cia.name
SELECT name
  FROM bbc JOIN cia ON bbc.name = cia.name