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This query also uses the column metadata in the Parquet files to infer the column names and data types of the result set. Queries can also automatically infer the column names of data from CSV files if there is a header row. However, there are times where you will want to explicitly define a schema to have more control of the data. Explicitly defining a schema also allows you to specify what columns you want to read from the files. You can define a schema for your data by adding a WITH clause with the column names and data types at the close of the OPENROWSET command. The following example uses the WITH clause to explicitly return three columns from the New York City yellow taxicab dataset.