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Altering Tables

This guide covers the SQL syntax for altering database tables by adding and modifying columns. To add a column, use the syntax `ALTER TABLE table_name ADD (column_name data_type, ...);`. For instance, to add a comments column to the s_region table, use `ALTER TABLE s_region ADD (comments VARCHAR2(255));`. To modify a column's data type, use `ALTER TABLE table_name MODIFY (column_name data_type, ...);`. You can also drop a column with the syntax `ALTER TABLE table_name DROP (column_name);`. These commands allow you to efficiently manage table structures.

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Altering Tables

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  1. Altering Tables

  2. Adding a Column: Syntax ALTER TABLE table ADD (column datatype , column datatype , ...);

  3. Adding a Column: Example ALTER TABLE s_region ADD (comments VARCHAR2(255)); Table altered.

  4. Modifying a Column: Syntax ALTER TABLE table MODIFY (column datatype, column datatype, ...);

  5. ALTER TABLE s_dept DROP name; Table altered.

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