Cubestore can't use round function because of type coercion error. Support 2 argument ROUND(num, precision).

[MrSpider]

Describe the bug

mysql> SELECT ROUND(1, 2);
ERROR 1815 (HY000): Error during planning: Coercion from [Int64, Int64] to the signature Uniform(1, [Float64, Float32]) failed.

To Reproduce

1. Start cubestore
2. Execute query SELECT ROUND(1, 2);

Expected behavior
Cubestore can use round function without errors.

Version:
Latest version (0.31.62)

Additional context
I tried to cast the arguments to a variety of different types, but the error message is always the same. I was not able to cast the input types to Float32 because float, real and double all result in Float64 when used.

Above is the minimal reproduction of the error we encountered, but our use case is to round the calculation of two different measurements inside a rollup join.

[paveltiunov]

@MrSpider ROUND function in Cube Store receives only one argument and always rounds to integer. For example ROUND(1.2).

[MrSpider]

Thanks for the information. It seems arrow datafusion added that functionality some time ago, but cubestore still uses an older version of the datafusion library, so hopefully sometime in the future it will be usable with two arguments.

[ranjeetranjan]

Getting Round
Option-1

`ROUND((${CUBE.spend}) / CAST(${CUBE.clicks} AS FLOAT64), 2)

    cpc: {
      sql: `ROUND((${CUBE.spend}) / CAST(${CUBE.clicks} AS FLOAT64), 2)`,
      type: `number`,
      title: `CPC`
    }, 
```
**Error**

`Internal: This feature is not implemented: Unsupported SQL type Custom(ObjectName([Ident { value: "FLOAT64", quote_style: None }]))`

**Option-2**

`ROUND((${CUBE.spend}) / CAST(${CUBE.clicks} AS FLOAT), 2)
`
**Error**
`Internal: Error during planning: Coercion from [Float64, Int64] to the signature Uniform(1, [Float64, Float32]) failed. `

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