How to modify the name of a table in Oracle
How to modify the table name in oracle: 1. Use the "ALTER TABLE table_name RENAME TO new_table_name;" statement; 2. Use the "RENAME table_name TO new_table_name;" statement.
The operating environment of this tutorial: Windows 7 system, Oracle 11g version, Dell G3 computer.
oracle modifies the name of the table (renames the table)
For an existing table, you can also modify its name. There are two syntax forms for renaming a table:
One is to use the ALTER TABLE statement, the syntax is as follows:
ALTER TABLE table_name RENAME TO new_table_name;
The other is to use the RENAME statement directly, the syntax is as follows:
RENAME table_name TO new_table_name;
Expand knowledge:
Modify the name of the column
The syntax for modifying the name of the column in the table is as follows:
ALTER TABLE table_name RENAME COLUMN column_name TO new_column_name;
For example, change the name of the birthday column in the person table to age, as follows:
SQL> ALTER TABLE person RENAME COLUMN birthday TO age;
The table has been changed.
Modify the data type of a column
The syntax for modifying the data type of a column in a table is as follows:
ALTER TABLE table_name MODIFY column_name new_data_type;
For example, change the data type of the age column in the person table to NUMBER(4), as follows:
SQL> ALTER TABLE person MODIFY age NUMBER(4);
The table has been changed.
Note: The alter ... modify
used here should be distinguished from the alter ... add
used to modify Oracle's table-level constraints. Don't get confused.
Recommended tutorial: "Oracle Tutorial"
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