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The most important part of this is the definition of mytableid:
- serial tells it:
- use an integer for storage
- create a SEQUENCE called mytable_mytableid_seq
- set the default value for the field as nextval('mytable_mytableid_seq')
- set the sequence attribute of the field to match
- associate the SEQUENCE with the TABLE (so it's dropped if the table is dropped)
- PRIMARY KEY tells it to create a primary key constraint called mytable_pkey with mytableid as the only component
Here are the resulting attributes of mytableid inside pgadmin:
The helpful thing here is that the connection between the field and the sequence provides an more descriptive syntax for retrieving the recently assigned sequence (rather than remembering that it's "tablename_columnname_seq", which could change in the future):
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