Wiki / Protocol Messages

Frontend/backend message directions, wire fields and same-version protocol definitions.

Reading PostgreSQL 18.6.

Find an entry GroupAll groupsBackend messages (32)Bidirectional messages (2)Frontend messages (19)Logical replication formats (20) Apply

73 entries; 72 recorded in PostgreSQL 18.6.

• AuthenticationCleartextPassword Backend messages

  AuthenticationCleartextPassword is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationGSS Backend messages

  AuthenticationGSS is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationGSSContinue Backend messages

  AuthenticationGSSContinue is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationKerberosV5 Backend messages

  AuthenticationKerberosV5 is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationMD5Password Backend messages

  AuthenticationMD5Password is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationOk Backend messages

  AuthenticationOk is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationSASL Backend messages

  AuthenticationSASL is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationSASLContinue Backend messages

  AuthenticationSASLContinue is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationSASLFinal Backend messages

  AuthenticationSASLFinal is a backend protocol message. Identifies the message as an authentication request.

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• AuthenticationSCMCredential Backend messages not in 18

  Not recorded in the selected version.

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• AuthenticationSSPI Backend messages

  AuthenticationSSPI is a backend protocol message. Identifies the message as an authentication request.

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• BackendKeyData Backend messages

  BackendKeyData is a backend protocol message. Identifies the message as cancellation key data. The frontend must save these values if it wishes to be able to issue CancelRequest messages later.

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• BindComplete Backend messages

  BindComplete is a backend protocol message. Identifies the message as a Bind-complete indicator.

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• CloseComplete Backend messages

  CloseComplete is a backend protocol message. Identifies the message as a Close-complete indicator.

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• CommandComplete Backend messages

  CommandComplete is a backend protocol message. Identifies the message as a command-completed response.

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• CopyBothResponse Backend messages

  CopyBothResponse is a backend protocol message. Identifies the message as a Start Copy Both response. This message is used only for Streaming Replication.

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• CopyInResponse Backend messages

  CopyInResponse is a backend protocol message. Identifies the message as a Start Copy In response. The frontend must now send copy-in data (if not prepared to do so, send a CopyFail message).

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• CopyOutResponse Backend messages

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

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• DataRow Backend messages

  DataRow is a backend protocol message. Identifies the message as a data row.

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• EmptyQueryResponse Backend messages

  EmptyQueryResponse is a backend protocol message. Identifies the message as a response to an empty query string. (This substitutes for CommandComplete.)

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• ErrorResponse Backend messages

  ErrorResponse is a backend protocol message. Identifies the message as an error.

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• FunctionCallResponse Backend messages

  FunctionCallResponse is a backend protocol message. Identifies the message as a function call result.

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• NegotiateProtocolVersion Backend messages

  NegotiateProtocolVersion is a backend protocol message. Identifies the message as a protocol version negotiation message.

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• NoData Backend messages

  NoData is a backend protocol message. Identifies the message as a no-data indicator.

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• NoticeResponse Backend messages

  NoticeResponse is a backend protocol message. Identifies the message as a notice.

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• NotificationResponse Backend messages

  NotificationResponse is a backend protocol message. Identifies the message as a notification response.

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• ParameterDescription Backend messages

  ParameterDescription is a backend protocol message. Identifies the message as a parameter description.

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• ParameterStatus Backend messages

  ParameterStatus is a backend protocol message. Identifies the message as a run-time parameter status report.

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• ParseComplete Backend messages

  ParseComplete is a backend protocol message. Identifies the message as a Parse-complete indicator.

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• PortalSuspended Backend messages

  PortalSuspended is a backend protocol message. Identifies the message as a portal-suspended indicator. Note this only appears if an Execute message's row-count limit was reached.

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• ReadyForQuery Backend messages

  ReadyForQuery is a backend protocol message. Identifies the message type. ReadyForQuery is sent whenever the backend is ready for a new query cycle.

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• RowDescription Backend messages

  RowDescription is a backend protocol message. Identifies the message as a row description.

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• CopyData Bidirectional messages

  CopyData is a bidirectional protocol message. Identifies the message as COPY data.

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• CopyDone Bidirectional messages

  CopyDone is a bidirectional protocol message. Identifies the message as a COPY -complete indicator.

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• Bind Frontend messages

  Bind is a frontend protocol message. Identifies the message as a Bind command.

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• CancelRequest Frontend messages

  CancelRequest is a frontend protocol message. Length of message contents in bytes, including self.

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• Close Frontend messages

  Close is a frontend protocol message. Identifies the message as a Close command.

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• CopyFail Frontend messages

  CopyFail is a frontend protocol message. Identifies the message as a COPY -failure indicator.

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• Describe Frontend messages

  Describe is a frontend protocol message. Identifies the message as a Describe command.

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• Execute Frontend messages

  Execute is a frontend protocol message. Identifies the message as an Execute command.

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• Flush Frontend messages

  Flush is a frontend protocol message. Identifies the message as a Flush command.

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• FunctionCall Frontend messages

  FunctionCall is a frontend protocol message. Identifies the message as a function call.

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• GSSENCRequest Frontend messages

  GSSENCRequest is a frontend protocol message. Length of message contents in bytes, including self.

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• GSSResponse Frontend messages

  GSSResponse is a frontend protocol message. Identifies the message as a GSSAPI or SSPI response. Note that this is also used for SASL and password response messages. The exact message type can be deduced from the context.

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• Parse Frontend messages

  Parse is a frontend protocol message. Identifies the message as a Parse command.

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• PasswordMessage Frontend messages

  PasswordMessage is a frontend protocol message. Identifies the message as a password response. Note that this is also used for GSSAPI, SSPI and SASL response messages. The exact message type can be deduced from the context.

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• Query Frontend messages

  Query is a frontend protocol message. Identifies the message as a simple query.

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• SASLInitialResponse Frontend messages

  SASLInitialResponse is a frontend protocol message. Identifies the message as an initial SASL response. Note that this is also used for GSSAPI, SSPI and password response messages. The exact message type is deduced from the context.

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• SASLResponse Frontend messages

  SASLResponse is a frontend protocol message. Identifies the message as a SASL response. Note that this is also used for GSSAPI, SSPI and password response messages. The exact message type can be deduced from the context.

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• SSLRequest Frontend messages

  SSLRequest is a frontend protocol message. Length of message contents in bytes, including self.

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• StartupMessage Frontend messages

  StartupMessage is a frontend protocol message. Length of message contents in bytes, including self.

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• Sync Frontend messages

  Sync is a frontend protocol message. Identifies the message as a Sync command.

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• Terminate Frontend messages

  Terminate is a frontend protocol message. Identifies the message as a termination.

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• Begin (logical replication) Logical replication formats

  Logical replication Begin format. Identifies the message as a begin message.

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• Begin Prepare (logical replication) Logical replication formats

  Logical replication Begin Prepare format. Identifies the message as the beginning of a prepared transaction message.

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• Commit (logical replication) Logical replication formats

  Logical replication Commit format. Identifies the message as a commit message.

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• Commit Prepared (logical replication) Logical replication formats

  Logical replication Commit Prepared format. Identifies the message as the commit of a prepared transaction message.

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• Delete (logical replication) Logical replication formats

  Logical replication Delete format. Identifies the message as a delete message.

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• Insert (logical replication) Logical replication formats

  Logical replication Insert format. Identifies the message as an insert message.

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• Message (logical replication) Logical replication formats

  Logical replication Message format. Identifies the message as a logical decoding message.

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• Origin (logical replication) Logical replication formats

  Logical replication Origin format. Identifies the message as an origin message.

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• Prepare (logical replication) Logical replication formats

  Logical replication Prepare format. Identifies the message as a prepared transaction message.

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• Relation (logical replication) Logical replication formats

  Logical replication Relation format. Identifies the message as a relation message.

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• Rollback Prepared (logical replication) Logical replication formats

  Logical replication Rollback Prepared format. Identifies the message as the rollback of a prepared transaction message.

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• Stream Abort (logical replication) Logical replication formats

  Logical replication Stream Abort format. Identifies the message as a stream abort message.

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• Stream Commit (logical replication) Logical replication formats

  Logical replication Stream Commit format. Identifies the message as a stream commit message.

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• Stream Prepare (logical replication) Logical replication formats

  Logical replication Stream Prepare format. Identifies the message as a stream prepared transaction message.

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• Stream Start (logical replication) Logical replication formats

  Logical replication Stream Start format. Identifies the message as a stream start message.

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• Stream Stop (logical replication) Logical replication formats

  Logical replication Stream Stop format. Identifies the message as a stream stop message.

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• Truncate (logical replication) Logical replication formats

  Logical replication Truncate format. Identifies the message as a truncate message.

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• TupleData (logical replication) Logical replication formats

  Logical replication TupleData format. Number of columns.

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• Type (logical replication) Logical replication formats

  Logical replication Type format. Identifies the message as a type message.

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• Update (logical replication) Logical replication formats

  Logical replication Update format. Identifies the message as an update message.

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RecordedFirst recordedInterface or attribute changeNo longer recorded

Squares indicate presence in sampled builds, not first introduction. Select a square for the same-version definition and sources.

Changes in PostgreSQL 18.6 · Export JSON

Reading this collection

Frontend/backend messages and logical-replication payload formats have separate identities. Complete definitions preserve conditional and repeating fields. Field-table positions are not byte offsets; flow sections describe valid exchanges.