f88306dd_enas_mais_um_blog_sobre_Oracle__Type_of_Limit
[Item] GROUP BY clause [Limit Value] The GROUP BY expression and all of the nondistinct aggregate functions (for example, SUM, AVG) must fit within a single database block. [Type of Limit] 
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Alessandro Guimarães - Oracle Blog | Apenas mais um blog sobre Oracle
Type of Limit