Altering tables and constraints

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Altering tables and constraints

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After you create your tables, you may need to change the table structures because you omitted a column, your column definition needs to be changed, or you want to enable or disable constraints. This lesson will demonstrate how you can amend table structures as well as add and remove constraints. At the end of this lesson, you should be able to  Add and modify table columns.  Add, enable, disable, or remove constraints.  Drop a table.  Remove all rows leaving the table definition intact.  Change object names.  Add comments to objects and view comments from the data dictionary....

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