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Bind
Bind is a frontend protocol message. Identifies the message as a Bind command.
Reading PostgreSQL 18.6.
Description
Bind is a frontend protocol message. Identifies the message as a Bind command.
- Direction
- Frontend → backend
- First wire field
- Byte1('B')
- Field entries
- 11
- Documented flow contexts
- Extended Query; Function Call
Usage
Bind (F)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('B') | Identifies the message as a Bind command. |
| 2 | Int32 | Length of message contents in bytes, including self. |
| 3 | String | The name of the destination portal (an empty string selects the unnamed portal). |
| 4 | String | The name of the source prepared statement (an empty string selects the unnamed prepared statement). |
| 5 | Int16 | The number of parameter format codes that follow (denoted C below). This can be zero to indicate that there are no parameters or that the parameters all use the default format (text); or one, in which case the specified format code is applied to all parameters; or it can equal the actual number of parameters. |
| 6 | Int16[ C ] | The parameter format codes. Each must presently be zero (text) or one (binary). |
| 7 | Int16 | The number of parameter values that follow (possibly zero). This must match the number of parameters needed by the query. |
| 8 | Int32 | The length of the parameter value, in bytes (this count does not include itself). Can be zero. As a special case, -1 indicates a NULL parameter value. No value bytes follow in the NULL case. |
| 9 | Byte n | The value of the parameter, in the format indicated by the associated format code. n is the above length. |
| 10 | Int16 | The number of result-column format codes that follow (denoted R below). This can be zero to indicate that there are no result columns or that the result columns should all use the default format (text); or one, in which case the specified format code is applied to all result columns (if any); or it can equal the actual number of result columns of the query. |
| 11 | Int16[ R ] | The result-column format codes. Each must presently be zero (text) or one (binary). |
Manual definition
-
- Byte1('B')
-
Identifies the message as a Bind command.
- Int32
-
Length of message contents in bytes, including self.
- String
-
The name of the destination portal (an empty string selects the unnamed portal).
- String
-
The name of the source prepared statement (an empty string selects the unnamed prepared statement).
- Int16
-
The number of parameter format codes that follow (denoted
Cbelow). This can be zero to indicate that there are no parameters or that the parameters all use the default format (text); or one, in which case the specified format code is applied to all parameters; or it can equal the actual number of parameters. - Int16[
C] -
The parameter format codes. Each must presently be zero (text) or one (binary).
- Int16
-
The number of parameter values that follow (possibly zero). This must match the number of parameters needed by the query.
Next, the following pair of fields appear for each parameter:
- Int32
-
The length of the parameter value, in bytes (this count does not include itself). Can be zero. As a special case, -1 indicates a NULL parameter value. No value bytes follow in the NULL case.
- Byte
n -
The value of the parameter, in the format indicated by the associated format code.
nis the above length.
After the last parameter, the following fields appear:
- Int16
-
The number of result-column format codes that follow (denoted
Rbelow). This can be zero to indicate that there are no result columns or that the result columns should all use the default format (text); or one, in which case the specified format code is applied to all result columns (if any); or it can equal the actual number of result columns of the query. - Int16[
R] -
The result-column format codes. Each must presently be zero (text) or one (binary).
Related entries
Documentation and source
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.