Enum BackendMessage 

pub enum BackendMessage {
    AuthenticationOk,
    AuthenticationCleartextPassword,
    AuthenticationMD5Password([u8; 4]),
    AuthenticationSASL(Vec<String>),
    AuthenticationSASLContinue(Vec<u8>),
    AuthenticationSASLFinal(Vec<u8>),
    BackendKeyData {
        process_id: i32,
        secret_key: i32,
    },
    ParameterStatus {
        name: String,
        value: String,
    },
    ReadyForQuery(TransactionStatus),
    RowDescription(Vec<FieldDescription>),
    DataRow(Vec<Option<Vec<u8>>>),
    CommandComplete(String),
    EmptyQueryResponse,
    ParseComplete,
    BindComplete,
    CloseComplete,
    ParameterDescription(Vec<u32>),
    NoData,
    PortalSuspended,
    ErrorResponse(ErrorFields),
    NoticeResponse(ErrorFields),
    CopyInResponse {
        format: i8,
        column_formats: Vec<i16>,
    },
    CopyOutResponse {
        format: i8,
        column_formats: Vec<i16>,
    },
    CopyData(Vec<u8>),
    CopyDone,
    CopyBothResponse {
        format: i8,
        column_formats: Vec<i16>,
    },
    NotificationResponse {
        process_id: i32,
        channel: String,
        payload: String,
    },
    FunctionCallResponse(Option<Vec<u8>>),
    NegotiateProtocolVersion {
        newest_minor: i32,
        unrecognized: Vec<String>,
    },
}

Messages sent from the PostgreSQL server to the client.

Variants

AuthenticationOk

Authentication successful

AuthenticationCleartextPassword

Server requests cleartext password

AuthenticationMD5Password([u8; 4])

Server requests MD5-hashed password with salt

AuthenticationSASL(Vec<String>)

Server requests SASL authentication (lists mechanisms)

AuthenticationSASLContinue(Vec<u8>)

SASL authentication continuation data

AuthenticationSASLFinal(Vec<u8>)

SASL authentication final data

BackendKeyData

Backend process ID and secret key for cancellation

Fields

process_id: i32

Process ID

secret_key: i32

Secret key

ParameterStatus

Server parameter status (e.g., server_encoding, TimeZone)

Fields

name: String

Parameter name

value: String

Parameter value

ReadyForQuery(TransactionStatus)

Server is ready for a new query

RowDescription(Vec<FieldDescription>)

Describes the columns of a result set

DataRow(Vec<Option<Vec<u8>>>)

A single data row

CommandComplete(String)

Query completed successfully

EmptyQueryResponse

Empty query response

ParseComplete

Parse completed successfully

BindComplete

Bind completed successfully

CloseComplete

Close completed successfully

ParameterDescription(Vec<u32>)

Describes parameter types for a prepared statement

NoData

No data will be returned

PortalSuspended

Portal execution suspended (reached max_rows)

ErrorResponse(ErrorFields)

Error response with details

NoticeResponse(ErrorFields)

Notice (warning) with details

CopyInResponse

Server is ready to receive COPY data

Fields

format: i8

Overall COPY format (0=text, 1=binary)

column_formats: Vec<i16>

Per-column format codes

CopyOutResponse

Server is sending COPY data

Fields

format: i8

Overall COPY format (0=text, 1=binary)

column_formats: Vec<i16>

Per-column format codes

CopyData(Vec<u8>)

COPY data chunk

CopyDone

COPY operation complete

CopyBothResponse

COPY data format information for both directions

Fields

format: i8

Overall COPY format (0=text, 1=binary)

column_formats: Vec<i16>

Per-column format codes

NotificationResponse

Asynchronous notification (from LISTEN/NOTIFY)

Fields

process_id: i32

Backend process ID that sent the notification

channel: String

Channel name

payload: String

Payload string

FunctionCallResponse(Option<Vec<u8>>)

Function call result

NegotiateProtocolVersion

Server doesn’t support requested protocol features

Fields

newest_minor: i32

Server’s newest supported minor version

unrecognized: Vec<String>

Unrecognized options

Trait Implementations

impl Clone for BackendMessage

fn clone(&self) -> BackendMessage

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BackendMessage

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for BackendMessage

fn eq(&self, other: &BackendMessage) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for BackendMessage