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CopyOutResponse

CopyOutResponse is a backend protocol message. Identifies the message as a Start Copy Out response. This message will be followed by copy-out data.

Reading PostgreSQL 18.6.

Description

CopyOutResponse is a backend protocol message. Identifies the message as a Start Copy Out response. This message will be followed by copy-out data.

Direction: Backend → frontend
First wire field: Byte1('H')
Field entries: 5
Documented flow contexts: Simple Query; COPY Operations

Usage

CopyOutResponse (B)

Framing and repetition

The complete definition below retains repetition, counts and conditional fields. A numbered table row is a documented field definition, not a fixed byte offset. Integer encodings and flow rules follow the same-version protocol chapter.

Wire fields in documented order

Position	Format	Meaning
1	Byte1('H')	Identifies the message as a Start Copy Out response. This message will be followed by copy-out data.
2	Int32	Length of message contents in bytes, including self.
3	Int8	0 indicates the overall COPY format is textual (rows separated by newlines, columns separated by separator characters, etc.). 1 indicates the overall copy format is binary (similar to DataRow format). See COPY for more information.
4	Int16	The number of columns in the data to be copied (denoted N below).
5	Int16[ N ]	The format codes to be used for each column. Each must presently be zero (text) or one (binary). All must be zero if the overall copy format is textual.

Manual definition

Byte1('H'): Identifies the message as a Start Copy Out response. This message will be followed by copy-out data.
Int32: Length of message contents in bytes, including self.
Int8: 0 indicates the overall COPY format is textual (rows separated by newlines, columns separated by separator characters, etc.). 1 indicates the overall copy format is binary (similar to DataRow format). See COPY for more information.
Int16: The number of columns in the data to be copied (denoted N below).
Int16[N]: The format codes to be used for each column. Each must presently be zero (text) or one (binary). All must be zero if the overall copy format is textual.

Related entries

Documentation and source

PostgreSQL 18 English manual

Source build

Version: 18.6
Build: https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2
Source fingerprint: 555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f

Compare versions

PostgreSQL 17 → 18: unchanged.

Compares recorded interfaces and attributes. Source fingerprints and build metadata are excluded; an absent sample is not proof of the introduction or removal release.

Related entries

Export JSON · Back to Protocol Messages · Recorded in PostgreSQL 10 through 20; the first sample is not necessarily its introduction.