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+# MockRecordReader
+
+Drill provides a mock record reader to generate test data in the package: `org.apache.drill.exec.store.mock`.
+
+Mock data is available for physical plans. Here is a typical example:
+
+```
+       {
+            @id:1,
+            pop:"mock-scan",
+            url: "http://apache.org",
+            entries:[
+                {records: 1000000, types: [
+                  {name: "blue", type: "INT", mode: "REQUIRED"},
+                  {name: "green", type: "INT", mode: "REQUIRED"}
+                ]}
+            ]
+        },
+```
+
+The JSON fields are:
+
+* `@id`: Standard required Physical OPerator (pop) ID.
+* `pop`: Must be `"mock-scan"`
+* `url`: Unused
+* `entries`: A list of schemas of the files to generate.
+
+The scanner supports parallelization based on the number of entries.
+
+The fields for the schema are:
+
+* `records`: The number of records to generate.
+* `types`: A list of columns (the "types" name is a misnomer.)
+
+Field schema fields include:
+
+* `name`: Field name
+* `type`: The Drill minor type as defined in `MinorType`.
+* `mode`: The cardinality (mode) as defined in `DataMode`: `OPTIONAL`, `REQUIRED` or `REPEATED`.
+* `width`: Optional field width (need only for variable-size types such as `VARCHAR`.)