Oracle Auto Increment: Creating Sequences Guide

When creating an auto-incrementing sequence in Oracle, there are a few key points to keep in mind:

1. The name of the sequence must be unique and cannot conflict with the names of other objects in the database.
2. The parameters such as the starting value, increment value, and maximum value of the sequence should be set according to actual needs. The starting value is the first value generated in the sequence, defaulting to 1; the increment value is the difference between each generated value and the previous one, defaulting to 1; the maximum value is the highest value the sequence can generate, defaulting to 10^27-1.
3. The sequence can be either looping or non-looping based on the requirements. Looping means that when the sequence reaches the maximum value, it will start generating new sequence values from the starting value again; non-looping means that the sequence cannot generate new values once it reaches the maximum value.
4. Sequences can be used in column definitions in a table, and by default, a sequence will automatically generate the next value each time data is inserted and assign it to the column.
5. Sequences’ permissions should be set based on actual needs, ensuring that only authorized users can access and modify them.
6. Before using a sequence, you need to create a sequence object first, and then modify the sequence parameters using the ALTER SEQUENCE statement or delete the sequence object using the DROP SEQUENCE statement.

In conclusion, when creating an auto-increment sequence, it is important to pay attention to issues such as naming, parameter settings, whether or not to use a loop, and permission control, in order to meet actual needs and ensure the correct use of the sequence.