Does auto increment have to be primary key?

This also applies to 0, unless the NO_AUTO_VALUE_ON_ZERO SQL_MODE is enabled. AUTO_INCREMENT columns start from 1 by default. Each table can have only one AUTO_INCREMENT column. It must defined as a key (not necessarily the PRIMARY KEY or UNIQUE key).

Does primary key auto increment SQLite?

On an INSERT, if the ROWID or INTEGER PRIMARY KEY column is not explicitly given a value, then it will be filled automatically with an unused integer, usually one more than the largest ROWID currently in use.

Why is Autoincrement bad?

The first reason not to use AutoNumber on each table is you may end up merging records from multiple tables. Say you have a Sales Order table and some other kind of order table, and you decide to pull out some common data and use multiple table inheritance. It’s nice to have primary keys that are globally unique.

Can UUID be primary key?

Pros. Using UUID for a primary key brings the following advantages: By using UUID, you can generate the primary key value of the parent table up front and insert rows into both parent and child tables at the same time within a transaction.

Does SQLite support enum?

SQLite does not support the enum data type directly, so we can use some encoded statement to implement the SQLite enum data type. Basically, the enum is used to store the group of elements in a single string. SQLite does support the enum data type, but it is very compact to store the data.

Does SQLite need a primary key?

You don’t need to define a primary key. By default, the table will have a key based on the rowid value. More information can be found in the documentation here.

Is UUID an overkill?

If you have strong storage constraints, UUIDs can cause a problem, since they use 2 to 4 times as many space as a serial or big serial. So if you have strong size constraints and if you don’t expose the primary keys, then UUIDs may be overkill.

Is UUID a good partition key?

2 Answers. UUID is a good choice for partition key – it should be good distributed between cluster nodes.

Is the autoincrement keyword always used in SQLite?

The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, and disk I/O overhead and should be avoided if not strictly needed. It is usually not needed. In SQLite, a column with type INTEGER PRIMARY KEY is an alias for the ROWID (except in WITHOUT ROWID tables) which is always a 64-bit signed integer.

What does an integer primary key do in SQLite?

In SQLite, a column with type INTEGER PRIMARY KEY is an alias for the ROWID (except in WITHOUT ROWID tables) which is always a 64-bit signed integer. On an INSERT , if the ROWID or INTEGER PRIMARY KEY column is not explicitly given a value, then it will be filled automatically with an unused integer, usually one more than the largest ROWID

When to use autoincrement after Integer Primary Key?

An integer primary key will indeed increment, however if the table drops all rows, it starts from the beginning again, It is important if you want to have all associated records tied correctly to use the autoincrement description after the primary key declaration on the integer field.

Why is autoincrement not allowed on without rowid table?

Because AUTOINCREMENT keyword changes the behavior of the ROWID selection algorithm, AUTOINCREMENT is not allowed on WITHOUT ROWID tables or on any table column other than INTEGER PRIMARY KEY. Any attempt to use AUTOINCREMENT on a WITHOUT ROWID table or on a column other than the INTEGER PRIMARY KEY column results in an error.