What Are The Restrictions On External Table Columns?

1.	What Are The Restrictions On External Table Columns?
Answer» When creating external table COLUMNS, you NEED to watch out some RESTRICTIONS: "PRIMARY KEY" is not allowed. "NOT NULL" is not allowed. "DEFAULT value" is not allowed. When creating external table columns, you need to watch out some restrictions:

Answer»

When creating external table COLUMNS, you NEED to watch out some RESTRICTIONS:

When creating external table columns, you need to watch out some restrictions:

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