Alter table add columns

[discord9]

What type of enhancement is this?

User experience

What does the enhancement do?

Support alter table add more columns(currently only support one) in sql parser. This is both helpful for User Experience and useful in testing, i.e.:(the syntax can change)

Alter Table Add Column l INTEGER DEFAULT 0,m INTEGER DEFAULT 0, n INTEGER DEFAULT 0;

Implementation challenges

None

[NiwakaDev]

I'd like to implement this feature.

[discord9]

I'd like to implement this feature.

Great! refer to AlterTableOperation::AddColumn and parse_alter_table for example of how to modify parser