hadoop - Perform sql join using sqlcontext spark -


i tried running query querying oracle db joins using sqlcontext like,

val sql="select b,c b.join=c.join" val dataframe = sqlcontext.read.jdbc(url,sql,connection_properties)

i getting invalid tablename error. if try querying table below works fine.

val df1 = sqlcontext.read.jdbc(url,"b",connection_properties) val df2 = sqlcontext.read.jdbc(url,"c",connection_properties)

will not possible run join queries using sqlcontext.

this need do, create 2 dataframes tables below 

val df1 = sqlcontext.read.jdbc(url,"b",connection_properties) val df2 = sqlcontext.read.jdbc(url,"c",connection_properties)

and join 2 dataframes key want join 

df1.join(df2, <join condition>, <which join>)  //example df1.join(df2, df1($"id") === df2($"id"), "left")

i think better option far know

hope helps!


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