SQL defines two primary character types: character and character varying. Postgres supports these types, in addition to the more general text type, which unlike character varying does not require an explicit declared upper limit on the size of the field.
Table 3-4. Postgres Character Types
Character Type
Storage
Recommendation
Description
character(n), char(n)
(4+n) bytes
SQL-compatible
Fixed-length blank padded
character varying(n), varchar(n)
(4+n) bytes
SQL-compatible
Variable-length with limit
text
(4+n) bytes
Most flexible
Variable unlimited length
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Text type is not unlimited but rather limited by tuple size of 8140 bytes.