Historically, a CSV file is stored in a database as one row, requiring a LOB data type. With NOS, each CSV file record is a single row in the foreign table.
- For UNICODE, that is equivalent to 8,388,096 characters.
- For LATIN, that is equivalent to 16,776,192 characters.
The actual record size is equivalent to the dataset individual record size.
NOS automatically discovers the schema of the data, including the data format, field delimiter, column names, column data types, and object store path definition.
If there are more columns than the number of fields in some of the records, then NULLs are returned for those columns. Similarly if there are less columns than the fields in some of the records, the extra fields are ignored.
For supported CSV formats, see CSV External Files.
For instructions on working with CSV files without headers, see the Orange Book, Native Object Store: Teradata Vantage™ Advanced SQL Engine, TDN0009800.