Oracle Database for the Data Type of database fields, oracle Data Type

Oracle Database for the Data Type of database fields, oracle Data Type
Modify the Data Type of Oracle Data Columns

Method 1:

// Create the same temporary table

Create table T_BUSINESS_MODEL_TEMP as select * from T_BUSINESS_MODEL where 1 = 2;

// Change the data type of the temporary table

Alter table T_BUSINESS_MODEL_TEMP modify MODEL_MONEY NUMBER (10, 2 );

// Assign the original table data to the latest Table

Insert into T_BUSINESS_MODEL_TEMP select * from T_BUSINESS_MODEL;

// Delete the original table

Drop table T_BUSINESS_MODEL;

// Rename the temporary table as the original table

Alter table T_BUSINESS_MODEL_TEMP rename to T_BUSINESS_MODEL;

// Add constraints of the original table (primary key, foreign key, index)

Alter table T_BUSINESS_MODEL
Add constraint PK_T_BUSINESS_MODEL primary key (ID );

Method 2:

-- Rename a field
Alter table PROJECT rename column NAME to NAME1;

----- Change the field name to the original name.
Alter table PROJECT add NAME VARCHAR2 (300 );
--- Assignment
Update PROJECT np
Set np. name = np. name1;
Commit;
--- Delete the original renamed Field
Alter table PROJECT drop column NAME1;

I think method 2 is better!