{
    head:{
        type:"APACHE_DRILL_PHYSICAL",
        version:"1",
        generator:{
            type:"manual"
        }
    },
    graph:[
        {
            @id:1,
            pop:"mock-sub-scan",
            url: "http://apache.org",
            entries:[
                {records: 1, types: [
                  {name: "float8Column", type: "FLOAT8", mode: "OPTIONAL"}
               ]}
            ]
        },
        {
            @id:2,
            child: 1,
        pop:"project",
          exprs: [
            { ref: "isNullOfNullExp", expr:"isnull(unkonwCol)" },
            { ref: "isNullOfKnowCol", expr:"isnull(float8Column)" },
            { ref: "isNotNullOfNullExp", expr:"isnotnull(unkonwCol)" },
            { ref: "isNotNullOfKnowCol", expr:"isnotnull(float8Column)" },
            { ref: "BigIntAddNullExp", expr:"1 + unknowCol" },
            { ref: "NullExpAddBigInt", expr:"unknowCol + 1" },
            { ref: "Float8AddNullExp", expr:"1.2 + unknowCol" },
            { ref: "NullExpAddFloat8", expr:"unknowCol + 1.2" },
            { ref: "Float4AddNullExp", expr:"cast(1.2 as float4) + unknowCol" },
            { ref: "NullExpAddFloat4", expr:"unknowCol +cast(1.2 as float4) " }
          ]
        },
        {
            @id: 3,
            child: 2,
            pop: "screen"
        }
    ]
}