What is the main problem of this implementation of a composite type based on the database TIMESTAMP without timezone Syntax error! NULL in code Lack of CTE readability Portability issues due to SERIAL "TICKET_TYPE" was not declared in the database Not the last value at the INTEGER level

The main issues in implementing composite types in a database can be as follows:

• Using TIMESTAMP without a time zone leads to ambiguity when working with time zones, which can cause errors in time interpretation.

• Syntax errors, such as using NULL where it is not expected, can cause failures when executing queries.

• The absence of CTEs (Common Table Expressions) reduces the readability and maintainability of complex queries.

• Using SERIAL for auto-increment reduces code portability across different DBMSs, as SERIAL is specific to PostgreSQL.

• Declaring an undeclared type "TICKET_TYPE" in the database will cause an error when attempting to use it.

• Using INTEGER to store values that may exceed the range can lead to overflow.

It is recommended to use TIMESTAMP WITH TIME ZONE, check syntax, apply CTEs for complex queries, use standardized data types, and explicitly declare all user-defined types.