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   _____    ______    _  __    _____    _____    
  / ___//  /_   _//  | |/ //  |  ___|| |  __ \\  
  \___ \\   -| ||-   | ' //   | ||__   | |  \ || 
  /    //   _| ||_   | . \\   | ||__   | |__/ || 
 /____//   /_____//  |_|\_\\  |_____|| |_____//  
`-----`    `-----`   `-` --`  `-----`   -----`

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Text this: On optimizing relational self-joins