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Package pgx

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The latest major version is v4.

Published: Jul 30, 2020 | License: MIT | Module:


Package pgx is a PostgreSQL database driver.

pgx provides lower level access to PostgreSQL than the standard database/sql. It remains as similar to the database/sql interface as possible while providing better speed and access to PostgreSQL specific features. Import to use pgx as a database/sql compatible driver.

Establishing a Connection

The primary way of establishing a connection is with `pgx.Connect`.

conn, err := pgx.Connect(context.Background(), os.Getenv("DATABASE_URL"))

The database connection string can be in URL or DSN format. Both PostgreSQL settings and pgx settings can be specified here. In addition, a config struct can be created by `ParseConfig` and modified before establishing the connection with `ConnectConfig`.

config, err := pgx.ParseConfig(os.Getenv("DATABASE_URL"))
if err != nil {
    // ...
config.Logger = log15adapter.NewLogger(log.New("module", "pgx"))

conn, err := pgx.ConnectConfig(context.Background(), config)

Connection Pool

`*pgx.Conn` represents a single connection to the database and is not concurrency safe. Use sub-package pgxpool for a concurrency safe connection pool.

Query Interface

pgx implements Query and Scan in the familiar database/sql style.

var sum int32

// Send the query to the server. The returned rows MUST be closed
// before conn can be used again.
rows, err := conn.Query(context.Background(), "select generate_series(1,$1)", 10)
if err != nil {
    return err

// rows.Close is called by rows.Next when all rows are read
// or an error occurs in Next or Scan. So it may optionally be
// omitted if nothing in the rows.Next loop can panic. It is
// safe to close rows multiple times.
defer rows.Close()

// Iterate through the result set
for rows.Next() {
    var n int32
    err = rows.Scan(&n)
    if err != nil {
        return err
    sum += n

// Any errors encountered by rows.Next or rows.Scan will be returned here
if rows.Err() != nil {
    return rows.Err()

// No errors found - do something with sum

pgx also implements QueryRow in the same style as database/sql.

var name string
var weight int64
err := conn.QueryRow(context.Background(), "select name, weight from widgets where id=$1", 42).Scan(&name, &weight)
if err != nil {
    return err

Use Exec to execute a query that does not return a result set.

commandTag, err := conn.Exec(context.Background(), "delete from widgets where id=$1", 42)
if err != nil {
    return err
if commandTag.RowsAffected() != 1 {
    return errors.New("No row found to delete")

Base Type Mapping

pgx maps between all common base types directly between Go and PostgreSQL. In particular:

Go           PostgreSQL
string       varchar

// Integers are automatically be converted to any other integer type if
// it can be done without overflow or underflow.
int16        smallint
int32        int
int64        bigint

// Floats are strict and do not automatically convert like integers.
float32      float4
float64      float8

time.Time   date

[]byte      bytea

Null Mapping

pgx can map nulls in two ways. The first is package pgtype provides types that have a data field and a status field. They work in a similar fashion to database/sql. The second is to use a pointer to a pointer.

var foo pgtype.Varchar
var bar *string
err := conn.QueryRow("select foo, bar from widgets where id=$1", 42).Scan(&foo, &bar)
if err != nil {
    return err

Array Mapping

pgx maps between int16, int32, int64, float32, float64, and string Go slices and the equivalent PostgreSQL array type. Go slices of native types do not support nulls, so if a PostgreSQL array that contains a null is read into a native Go slice an error will occur. The pgtype package includes many more array types for PostgreSQL types that do not directly map to native Go types.

JSON and JSONB Mapping

pgx includes built-in support to marshal and unmarshal between Go types and the PostgreSQL JSON and JSONB.

Inet and CIDR Mapping

pgx encodes from net.IPNet to and from inet and cidr PostgreSQL types. In addition, as a convenience pgx will encode from a net.IP; it will assume a /32 netmask for IPv4 and a /128 for IPv6.

Custom Type Support

pgx includes support for the common data types like integers, floats, strings, dates, and times that have direct mappings between Go and SQL. In addition, pgx uses the library to support more types. See documention for that library for instructions on how to implement custom types.

See example_custom_type_test.go for an example of a custom type for the PostgreSQL point type.

pgx also includes support for custom types implementing the database/sql.Scanner and database/sql/driver.Valuer interfaces.

If pgx does cannot natively encode a type and that type is a renamed type (e.g. type MyTime time.Time) pgx will attempt to encode the underlying type. While this is usually desired behavior it can produce surprising behavior if one the underlying type and the renamed type each implement database/sql interfaces and the other implements pgx interfaces. It is recommended that this situation be avoided by implementing pgx interfaces on the renamed type.

Composite types and row values

Row values and composite types are represented as pgtype.Record ( It is possible to get values of your custom type by implementing DecodeBinary interface. Decoding into pgtype.Record first can simplify process by avoiding dealing with raw protocol directly.

For example:

type MyType struct {
    a int      // NULL will cause decoding error
    b *string  // there can be NULL in this position in SQL

func (t *MyType) DecodeBinary(ci *pgtype.ConnInfo, src []byte) error {
    r := pgtype.Record{
        Fields: []pgtype.Value{&pgtype.Int4{}, &pgtype.Text{}},

    if err := r.DecodeBinary(ci, src); err != nil {
        return err

    if r.Status != pgtype.Present {
        return errors.New("BUG: decoding should not be called on NULL value")

    a := r.Fields[0].(*pgtype.Int4)
    b := r.Fields[1].(*pgtype.Text)

    // type compatibility is checked by AssignTo
    // only lossless assignments will succeed
    if err := a.AssignTo(&t.a); err != nil {
        return err

    // AssignTo also deals with null value handling
    if err := b.AssignTo(&t.b); err != nil {
        return err
    return nil

result := MyType{}
err := conn.QueryRow(context.Background(), "select row(1, 'foo'::text)", pgx.QueryResultFormats{pgx.BinaryFormatCode}).Scan(&r)

Raw Bytes Mapping

[]byte passed as arguments to Query, QueryRow, and Exec are passed unmodified to PostgreSQL.


Transactions are started by calling Begin.

tx, err := conn.Begin(context.Background())
if err != nil {
    return err
// Rollback is safe to call even if the tx is already closed, so if
// the tx commits successfully, this is a no-op
defer tx.Rollback(context.Background())

_, err = tx.Exec(context.Background(), "insert into foo(id) values (1)")
if err != nil {
    return err

err = tx.Commit(context.Background())
if err != nil {
    return err

The Tx returned from Begin also implements the Begin method. This can be used to implement pseudo nested transactions. These are internally implemented with savepoints.

Use BeginTx to control the transaction mode.

Prepared Statements

Prepared statements can be manually created with the Prepare method. However, this is rarely necessary because pgx includes an automatic statement cache by default. Queries run through the normal Query, QueryRow, and Exec functions are automatically prepared on first execution and the prepared statement is reused on subsequent executions. See ParseConfig for information on how to customize or disable the statement cache.

Copy Protocol

Use CopyFrom to efficiently insert multiple rows at a time using the PostgreSQL copy protocol. CopyFrom accepts a CopyFromSource interface. If the data is already in a [][]interface{} use CopyFromRows to wrap it in a CopyFromSource interface. Or implement CopyFromSource to avoid buffering the entire data set in memory.

rows := [][]interface{}{
    {"John", "Smith", int32(36)},
    {"Jane", "Doe", int32(29)},

copyCount, err := conn.CopyFrom(
    []string{"first_name", "last_name", "age"},

CopyFrom can be faster than an insert with as few as 5 rows.

Listen and Notify

pgx can listen to the PostgreSQL notification system with the `Conn.WaitForNotification` method. It blocks until a context is received or the context is canceled.

_, err := conn.Exec(context.Background(), "listen channelname")
if err != nil {
    return nil

if notification, err := conn.WaitForNotification(context.Background()); err != nil {
    // do something with notification


pgx defines a simple logger interface. Connections optionally accept a logger that satisfies this interface. Set LogLevel to control logging verbosity. Adapters for,,,, and the testing log are provided in the log directory.

Lower Level PostgreSQL Functionality

pgx is implemented on top of a lower level PostgreSQL driver. The Conn.PgConn() method can be used to access this lower layer.


pgx is compatible with PgBouncer in two modes. One is when the connection has a statement cache in "describe" mode. The other is when the connection is using the simple protocol. This can be set with the PreferSimpleProtocol config option.



const (
	LogLevelTrace = 6
	LogLevelDebug = 5
	LogLevelInfo  = 4
	LogLevelWarn  = 3
	LogLevelError = 2
	LogLevelNone  = 1

The values for log levels are chosen such that the zero value means that no log level was specified.

const (
	Serializable    = TxIsoLevel("serializable")
	RepeatableRead  = TxIsoLevel("repeatable read")
	ReadCommitted   = TxIsoLevel("read committed")
	ReadUncommitted = TxIsoLevel("read uncommitted")

Transaction isolation levels

const (
	ReadWrite = TxAccessMode("read write")
	ReadOnly  = TxAccessMode("read only")

Transaction access modes

const (
	Deferrable    = TxDeferrableMode("deferrable")
	NotDeferrable = TxDeferrableMode("not deferrable")

Transaction deferrable modes

const (
	TextFormatCode   = 0
	BinaryFormatCode = 1

PostgreSQL format codes


var ErrInvalidLogLevel = errors.New("invalid log level")

ErrInvalidLogLevel occurs on attempt to set an invalid log level.

var ErrNoRows = errors.New("no rows in result set")

ErrNoRows occurs when rows are expected but none are returned.

var ErrTxClosed = errors.New("tx is closed")
var ErrTxCommitRollback = errors.New("commit unexpectedly resulted in rollback")

ErrTxCommitRollback occurs when an error has occurred in a transaction and Commit() is called. PostgreSQL accepts COMMIT on aborted transactions, but it is treated as ROLLBACK.

func ScanRow

func ScanRow(connInfo *pgtype.ConnInfo, fieldDescriptions []pgproto3.FieldDescription, values [][]byte, dest ...interface{}) error

ScanRow decodes raw row data into dest. It can be used to scan rows read from the lower level pgconn interface.

connInfo - OID to Go type mapping. fieldDescriptions - OID and format of values values - the raw data as returned from the PostgreSQL server dest - the destination that values will be decoded into

type Batch

type Batch struct {
	// contains filtered or unexported fields

Batch queries are a way of bundling multiple queries together to avoid unnecessary network round trips.

func (*Batch) Len

func (b *Batch) Len() int

Len returns number of queries that have been queued so far.

func (*Batch) Queue

func (b *Batch) Queue(query string, arguments ...interface{})

Queue queues a query to batch b. query can be an SQL query or the name of a prepared statement.

type BatchResults

type BatchResults interface {
	// Exec reads the results from the next query in the batch as if the query has been sent with Conn.Exec.
	Exec() (pgconn.CommandTag, error)

	// Query reads the results from the next query in the batch as if the query has been sent with Conn.Query.
	Query() (Rows, error)

	// QueryRow reads the results from the next query in the batch as if the query has been sent with Conn.QueryRow.
	QueryRow() Row

	// Close closes the batch operation. This must be called before the underlying connection can be used again. Any error
	// that occurred during a batch operation may have made it impossible to resyncronize the connection with the server.
	// In this case the underlying connection will have been closed.
	Close() error

type BuildStatementCacheFunc

type BuildStatementCacheFunc func(conn *pgconn.PgConn) stmtcache.Cache

BuildStatementCacheFunc is a function that can be used to create a stmtcache.Cache implementation for connection.

type Conn

type Conn struct {
	// contains filtered or unexported fields

Conn is a PostgreSQL connection handle. It is not safe for concurrent usage. Use a connection pool to manage access to multiple database connections from multiple goroutines.

func Connect

func Connect(ctx context.Context, connString string) (*Conn, error)

Connect establishes a connection with a PostgreSQL server with a connection string. See pgconn.Connect for details.

func ConnectConfig

func ConnectConfig(ctx context.Context, connConfig *ConnConfig) (*Conn, error)

Connect establishes a connection with a PostgreSQL server with a configuration struct. connConfig must have been created by ParseConfig.

func (*Conn) Begin

func (c *Conn) Begin(ctx context.Context) (Tx, error)

Begin starts a transaction. Unlike database/sql, the context only affects the begin command. i.e. there is no auto-rollback on context cancellation.

func (*Conn) BeginTx

func (c *Conn) BeginTx(ctx context.Context, txOptions TxOptions) (Tx, error)

BeginTx starts a transaction with txOptions determining the transaction mode. Unlike database/sql, the context only affects the begin command. i.e. there is no auto-rollback on context cancellation.

func (*Conn) Close

func (c *Conn) Close(ctx context.Context) error

Close closes a connection. It is safe to call Close on a already closed connection.

func (*Conn) Config

func (c *Conn) Config() *ConnConfig

Config returns a copy of config that was used to establish this connection.

func (*Conn) ConnInfo

func (c *Conn) ConnInfo() *pgtype.ConnInfo

ConnInfo returns the connection info used for this connection.

func (*Conn) CopyFrom

func (c *Conn) CopyFrom(ctx context.Context, tableName Identifier, columnNames []string, rowSrc CopyFromSource) (int64, error)

CopyFrom uses the PostgreSQL copy protocol to perform bulk data insertion. It returns the number of rows copied and an error.

CopyFrom requires all values use the binary format. Almost all types implemented by pgx use the binary format by default. Types implementing Encoder can only be used if they encode to the binary format.

func (*Conn) Deallocate

func (c *Conn) Deallocate(ctx context.Context, name string) error

Deallocate released a prepared statement

func (*Conn) Exec

func (c *Conn) Exec(ctx context.Context, sql string, arguments ...interface{}) (pgconn.CommandTag, error)

Exec executes sql. sql can be either a prepared statement name or an SQL string. arguments should be referenced positionally from the sql string as $1, $2, etc.

func (*Conn) IsClosed

func (c *Conn) IsClosed() bool

func (*Conn) PgConn

func (c *Conn) PgConn() *pgconn.PgConn

PgConn returns the underlying *pgconn.PgConn. This is an escape hatch method that allows lower level access to the PostgreSQL connection than pgx exposes.

It is strongly recommended that the connection be idle (no in-progress queries) before the underlying *pgconn.PgConn is used and the connection must be returned to the same state before any *pgx.Conn methods are again used.

func (*Conn) Ping

func (c *Conn) Ping(ctx context.Context) error

func (*Conn) Prepare

func (c *Conn) Prepare(ctx context.Context, name, sql string) (sd *pgconn.StatementDescription, err error)

Prepare creates a prepared statement with name and sql. sql can contain placeholders for bound parameters. These placeholders are referenced positional as $1, $2, etc.

Prepare is idempotent; i.e. it is safe to call Prepare multiple times with the same name and sql arguments. This allows a code path to Prepare and Query/Exec without concern for if the statement has already been prepared.

func (*Conn) Query

func (c *Conn) Query(ctx context.Context, sql string, args ...interface{}) (Rows, error)

Query executes sql with args. If there is an error the returned Rows will be returned in an error state. So it is allowed to ignore the error returned from Query and handle it in Rows.

For extra control over how the query is executed, the types QuerySimpleProtocol, QueryResultFormats, and QueryResultFormatsByOID may be used as the first args to control exactly how the query is executed. This is rarely needed. See the documentation for those types for details.

func (*Conn) QueryRow

func (c *Conn) QueryRow(ctx context.Context, sql string, args ...interface{}) Row

QueryRow is a convenience wrapper over Query. Any error that occurs while querying is deferred until calling Scan on the returned Row. That Row will error with ErrNoRows if no rows are returned.

func (*Conn) SendBatch

func (c *Conn) SendBatch(ctx context.Context, b *Batch) BatchResults

SendBatch sends all queued queries to the server at once. All queries are run in an implicit transaction unless explicit transaction control statements are executed. The returned BatchResults must be closed before the connection is used again.

func (*Conn) StatementCache

func (c *Conn) StatementCache() stmtcache.Cache

StatementCache returns the statement cache used for this connection.

func (*Conn) WaitForNotification

func (c *Conn) WaitForNotification(ctx context.Context) (*pgconn.Notification, error)

WaitForNotification waits for a PostgreSQL notification. It wraps the underlying pgconn notification system in a slightly more convenient form.

type ConnConfig

type ConnConfig struct {
	Logger   Logger
	LogLevel LogLevel

	// BuildStatementCache creates the stmtcache.Cache implementation for connections created with this config. Set
	// to nil to disable automatic prepared statements.
	BuildStatementCache BuildStatementCacheFunc

	// PreferSimpleProtocol disables implicit prepared statement usage. By default pgx automatically uses the extended
	// protocol. This can improve performance due to being able to use the binary format. It also does not rely on client
	// side parameter sanitization. However, it does incur two round-trips per query (unless using a prepared statement)
	// and may be incompatible proxies such as PGBouncer. Setting PreferSimpleProtocol causes the simple protocol to be
	// used by default. The same functionality can be controlled on a per query basis by setting
	// QueryExOptions.SimpleProtocol.
	PreferSimpleProtocol bool
	// contains filtered or unexported fields

ConnConfig contains all the options used to establish a connection. It must be created by ParseConfig and then it can be modified. A manually initialized ConnConfig will cause ConnectConfig to panic.

func ParseConfig

func ParseConfig(connString string) (*ConnConfig, error)

ParseConfig creates a ConnConfig from a connection string. ParseConfig handles all options that pgconn.ParseConfig does. In addition, it accepts the following options:

	The maximum size of the automatic statement cache. Set to 0 to disable automatic statement caching. Default: 512.

	Possible values: "prepare" and "describe". "prepare" will create prepared statements on the PostgreSQL server.
	"describe" will use the anonymous prepared statement to describe a statement without creating a statement on the
	server. "describe" is primarily useful when the environment does not allow prepared statements such as when
	running a connection pooler like PgBouncer. Default: "prepare"

func (*ConnConfig) ConnString

func (cc *ConnConfig) ConnString() string

func (*ConnConfig) Copy

func (cc *ConnConfig) Copy() *ConnConfig

Copy returns a deep copy of the config that is safe to use and modify. The only exception is the tls.Config: according to the tls.Config docs it must not be modified after creation.

type CopyFromSource

type CopyFromSource interface {
	// Next returns true if there is another row and makes the next row data
	// available to Values(). When there are no more rows available or an error
	// has occurred it returns false.
	Next() bool

	// Values returns the values for the current row.
	Values() ([]interface{}, error)

	// Err returns any error that has been encountered by the CopyFromSource. If
	// this is not nil *Conn.CopyFrom will abort the copy.
	Err() error

CopyFromSource is the interface used by *Conn.CopyFrom as the source for copy data.

func CopyFromRows

func CopyFromRows(rows [][]interface{}) CopyFromSource

CopyFromRows returns a CopyFromSource interface over the provided rows slice making it usable by *Conn.CopyFrom.

type Identifier

type Identifier []string

Identifier a PostgreSQL identifier or name. Identifiers can be composed of multiple parts such as ["schema", "table"] or ["table", "column"].

func (Identifier) Sanitize

func (ident Identifier) Sanitize() string

Sanitize returns a sanitized string safe for SQL interpolation.

type LargeObject

type LargeObject struct {
	// contains filtered or unexported fields

A LargeObject is a large object stored on the server. It is only valid within the transaction that it was initialized in. It uses the context it was initialized with for all operations. It implements these interfaces:


func (*LargeObject) Close

func (o *LargeObject) Close() error

Close closees the large object descriptor.

func (*LargeObject) Read

func (o *LargeObject) Read(p []byte) (int, error)

Read reads up to len(p) bytes into p returning the number of bytes read.

func (*LargeObject) Seek

func (o *LargeObject) Seek(offset int64, whence int) (n int64, err error)

Seek moves the current location pointer to the new location specified by offset.

func (*LargeObject) Tell

func (o *LargeObject) Tell() (n int64, err error)

Tell returns the current read or write location of the large object descriptor.

func (*LargeObject) Truncate

func (o *LargeObject) Truncate(size int64) (err error)

Trunctes the large object to size.

func (*LargeObject) Write

func (o *LargeObject) Write(p []byte) (int, error)

Write writes p to the large object and returns the number of bytes written and an error if not all of p was written.

type LargeObjectMode

type LargeObjectMode int32
const (
	LargeObjectModeWrite LargeObjectMode = 0x20000
	LargeObjectModeRead  LargeObjectMode = 0x40000

type LargeObjects

type LargeObjects struct {
	// contains filtered or unexported fields

LargeObjects is a structure used to access the large objects API. It is only valid within the transaction where it was created.

For more details see:

func (*LargeObjects) Create

func (o *LargeObjects) Create(ctx context.Context, oid uint32) (uint32, error)

Create creates a new large object. If oid is zero, the server assigns an unused OID.

func (*LargeObjects) Open

func (o *LargeObjects) Open(ctx context.Context, oid uint32, mode LargeObjectMode) (*LargeObject, error)

Open opens an existing large object with the given mode. ctx will also be used for all operations on the opened large object.

func (o *LargeObjects) Unlink(ctx context.Context, oid uint32) error

Unlink removes a large object from the database.

type LogLevel

type LogLevel int

LogLevel represents the pgx logging level. See LogLevel* constants for possible values.

func LogLevelFromString

func LogLevelFromString(s string) (LogLevel, error)

LogLevelFromString converts log level string to constant

Valid levels:


func (LogLevel) String

func (ll LogLevel) String() string

type Logger

type Logger interface {
	// Log a message at the given level with data key/value pairs. data may be nil.
	Log(ctx context.Context, level LogLevel, msg string, data map[string]interface{})

Logger is the interface used to get logging from pgx internals.

type QueryResultFormats

type QueryResultFormats []int16

QueryResultFormats controls the result format (text=0, binary=1) of a query by result column position.

type QueryResultFormatsByOID

type QueryResultFormatsByOID map[uint32]int16

QueryResultFormatsByOID controls the result format (text=0, binary=1) of a query by the result column OID.

type QuerySimpleProtocol

type QuerySimpleProtocol bool

QuerySimpleProtocol controls whether the simple or extended protocol is used to send the query.

type Row

type Row interface {
	// Scan works the same as Rows. with the following exceptions. If no
	// rows were found it returns ErrNoRows. If multiple rows are returned it
	// ignores all but the first.
	Scan(dest ...interface{}) error

Row is a convenience wrapper over Rows that is returned by QueryRow.

Row is an interface instead of a struct to allow tests to mock QueryRow. However, adding a method to an interface is technically a breaking change. Because of this the Row interface is partially excluded from semantic version requirements. Methods will not be removed or changed, but new methods may be added.

type Rows

type Rows interface {
	// Close closes the rows, making the connection ready for use again. It is safe
	// to call Close after rows is already closed.

	// Err returns any error that occurred while reading.
	Err() error

	// CommandTag returns the command tag from this query. It is only available after Rows is closed.
	CommandTag() pgconn.CommandTag

	FieldDescriptions() []pgproto3.FieldDescription

	// Next prepares the next row for reading. It returns true if there is another
	// row and false if no more rows are available. It automatically closes rows
	// when all rows are read.
	Next() bool

	// Scan reads the values from the current row into dest values positionally.
	// dest can include pointers to core types, values implementing the Scanner
	// interface, []byte, and nil. []byte will skip the decoding process and directly
	// copy the raw bytes received from PostgreSQL. nil will skip the value entirely.
	Scan(dest ...interface{}) error

	// Values returns the decoded row values.
	Values() ([]interface{}, error)

	// RawValues returns the unparsed bytes of the row values. The returned [][]byte is only valid until the next Next
	// call or the Rows is closed. However, the underlying byte data is safe to retain a reference to and mutate.
	RawValues() [][]byte

Rows is the result set returned from *Conn.Query. Rows must be closed before the *Conn can be used again. Rows are closed by explicitly calling Close(), calling Next() until it returns false, or when a fatal error occurs.

Once a Rows is closed the only methods that may be called are Close(), Err(), and CommandTag().

Rows is an interface instead of a struct to allow tests to mock Query. However, adding a method to an interface is technically a breaking change. Because of this the Rows interface is partially excluded from semantic version requirements. Methods will not be removed or changed, but new methods may be added.

type SerializationError

type SerializationError string

SerializationError occurs on failure to encode or decode a value

func (SerializationError) Error

func (e SerializationError) Error() string

type Tx

type Tx interface {
	// Begin starts a pseudo nested transaction.
	Begin(ctx context.Context) (Tx, error)

	// Commit commits the transaction if this is a real transaction or releases the savepoint if this is a pseudo nested
	// transaction. Commit will return ErrTxClosed if the Tx is already closed, but is otherwise safe to call multiple
	// times. If the commit fails with a rollback status (e.g. the transaction was already in a broken state) then
	// ErrTxCommitRollback will be returned.
	Commit(ctx context.Context) error

	// Rollback rolls back the transaction if this is a real transaction or rolls back to the savepoint if this is a
	// pseudo nested transaction. Rollback will return ErrTxClosed if the Tx is already closed, but is otherwise safe to
	// call multiple times. Hence, a defer tx.Rollback() is safe even if tx.Commit() will be called first in a non-error
	// condition. Any other failure of a real transaction will result in the connection being closed.
	Rollback(ctx context.Context) error

	CopyFrom(ctx context.Context, tableName Identifier, columnNames []string, rowSrc CopyFromSource) (int64, error)
	SendBatch(ctx context.Context, b *Batch) BatchResults
	LargeObjects() LargeObjects

	Prepare(ctx context.Context, name, sql string) (*pgconn.StatementDescription, error)

	Exec(ctx context.Context, sql string, arguments ...interface{}) (commandTag pgconn.CommandTag, err error)
	Query(ctx context.Context, sql string, args ...interface{}) (Rows, error)
	QueryRow(ctx context.Context, sql string, args ...interface{}) Row

	// Conn returns the underlying *Conn that on which this transaction is executing.
	Conn() *Conn

Tx represents a database transaction.

Tx is an interface instead of a struct to enable connection pools to be implemented without relying on internal pgx state, to support pseudo-nested transactions with savepoints, and to allow tests to mock transactions. However, adding a method to an interface is technically a breaking change. If new methods are added to Conn it may be desirable to add them to Tx as well. Because of this the Tx interface is partially excluded from semantic version requirements. Methods will not be removed or changed, but new methods may be added.

type TxAccessMode

type TxAccessMode string

type TxDeferrableMode

type TxDeferrableMode string

type TxIsoLevel

type TxIsoLevel string

type TxOptions

type TxOptions struct {
	IsoLevel       TxIsoLevel
	AccessMode     TxAccessMode
	DeferrableMode TxDeferrableMode

Package Files

Documentation was rendered with GOOS=linux and GOARCH=amd64.

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