Creating a table with data from another table is a common task in database management. This can be achieved using the SELECT ... INTO statement in Oracle SQL.
Syntax of the SELECT ... INTO Statement
SQL
SELECT column1, column2, ...
INTO new_table_name
FROM old_table_name
WHERE condition;
column1, column2, ...`: The columns to be selected from the old table.
new_table_name: The name of the new table to be created.
old_table_name: The name of the existing table.
WHERE: An optional condition to filter the data.
Example: Creating a New Table from the Students Table
Let's assume we have a Students table with the following columns:
Student_ID
Student_Name
Address
Phone
City
District
State
To create a new table named Active_Students containing only students from a specific city (e.g., "New York"), we can use the following SQL statement:
SQL
SELECT Student_ID, Student_Name, Address, Phone, City, District, State
INTO Active_Students
FROM Students
WHERE City = 'New York';
This will create a new table named Active_Students with the same structure as the Students table, but containing only the rows where the City is "New York".
Additional Considerations
Constraints: You can define constraints for the new table using the CREATE TABLE syntax within the SELECT ... INTO statement.
Data Types: Ensure that the data types for the columns in the new table match the corresponding data types in the old table.
Indexes: Consider creating indexes on frequently queried columns in the new table to improve performance.
Privileges: Make sure you have the necessary privileges to create tables and select data from the old table.
By using the SELECT ... INTO statement, you can efficiently create new tables based on existing data and customize the structure and content to meet your specific requirements.
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