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Variables can be computed using the following syntax in the cols parameter, variableName:computationExpression. The following will show you practical examples for a number of the supported operations described above.
Code Block title Addition http://{host}/rds/{collection}/{view}/select?cols=newVar:Var1+Var2
Code Block title Multiplication http://{host}/rds/{collection}/{view}/select?cols=newVar:Var1*Var2
Code Block title Square Root http://{host}/rds/{collection}/{view}/select?cols=newVar:SQRT(Var1)