September 26, 2024: PostgreSQL 17 Released!
Supported Versions: Current (17) / 16 / 15 / 14 / 13 / 12
Development Versions: devel
Unsupported versions: 11 / 10 / 9.6 / 9.5 / 9.4 / 9.3 / 9.2 / 9.1 / 9.0 / 8.4 / 8.3 / 8.2 / 8.1 / 8.0 / 7.4 / 7.3 / 7.2 / 7.1

52.6. Message Data Types

This section describes the base data types used in messages.

Intn(i)

An n-bit integer in network byte order (most significant byte first). If i is specified it is the exact value that will appear, otherwise the value is variable. Eg. Int16, Int32(42).

Intn[k]

An array of k n-bit integers, each in network byte order. The array length k is always determined by an earlier field in the message. Eg. Int16[M].

String(s)

A null-terminated string (C-style string). There is no specific length limitation on strings. If s is specified it is the exact value that will appear, otherwise the value is variable. Eg. String, String("user").

Note

There is no predefined limit on the length of a string that can be returned by the backend. Good coding strategy for a frontend is to use an expandable buffer so that anything that fits in memory can be accepted. If that's not feasible, read the full string and discard trailing characters that don't fit into your fixed-size buffer.

Byten(c)

Exactly n bytes. If the field width n is not a constant, it is always determinable from an earlier field in the message. If c is specified it is the exact value. Eg. Byte2, Byte1('\n').

Submit correction

If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.