PL/SQL :: Oracle SQL Template To Create Re-usable DDL / DML Scripts For Oracle Database

I have a requirement to put together a Oracle SQL template to create re-usable DDL/DML Scripts for Oracle databases.Only the Oracle DBA will be running the scripts so permissions is not an issue.

The workflow for any DDL is as follows:-

1) New Table

a. Check if the table exists from the system/admin views.

b. If table exists then give message "Table Exists"

c. If table does not exist then execute DDL code

2) Add Column

a. Check if Column exists for a given table from system/admin views

b. If column exists in the specified table,

b1. backup table.

b2. alter table to make changes to the column

b3. verify data or execute dml script convert from backup to the new change.

c. If Column does not exist

c1. backup table

c2. alter table to add column

c3. execute dml to populate column with default value.

The DML scripts are for populating base tables with data required for business operations.

3) Add new row

a. check if row exists by comparing old values of each column with new values to be added for the new record.

b. If exists, give message row exists

c. If not exists, add new record.

4) Update existing record (We have createtime columns in these tables so changes can be tracked)

a. check if row exists using primary key.

b. If exists,

b1. deactivate the record using the "active" column of the table

b2. Add new record with the changes required.

c. If does not exist, add new record with the changes required.