Pg to bun (#148)

* start moving to bun

* changing more stuff

* more

* and yet more

* tests passing

* seems stable now

* more big changes

* small fix

* little fixes

vendor/github.com/jackc/pgx/v4/stdlib/sql.go

@@ -0,0 +1,858 @@
+// Package stdlib is the compatibility layer from pgx to database/sql.
+//
+// A database/sql connection can be established through sql.Open.
+//
+//	db, err := sql.Open("pgx", "postgres://pgx_md5:secret@localhost:5432/pgx_test?sslmode=disable")
+//	if err != nil {
+//		return err
+//	}
+//
+// Or from a DSN string.
+//
+//	db, err := sql.Open("pgx", "user=postgres password=secret host=localhost port=5432 database=pgx_test sslmode=disable")
+//	if err != nil {
+//		return err
+//	}
+//
+// Or a pgx.ConnConfig can be used to set configuration not accessible via connection string. In this case the
+// pgx.ConnConfig must first be registered with the driver. This registration returns a connection string which is used
+// with sql.Open.
+//
+//	connConfig, _ := pgx.ParseConfig(os.Getenv("DATABASE_URL"))
+//	connConfig.Logger = myLogger
+//	connStr := stdlib.RegisterConnConfig(connConfig)
+//	db, _ := sql.Open("pgx", connStr)
+//
+// pgx uses standard PostgreSQL positional parameters in queries. e.g. $1, $2.
+// It does not support named parameters.
+//
+//	db.QueryRow("select * from users where id=$1", userID)
+//
+// In Go 1.13 and above (*sql.Conn) Raw() can be used to get a *pgx.Conn from the standard
+// database/sql.DB connection pool. This allows operations that use pgx specific functionality.
+//
+//	// Given db is a *sql.DB
+//	conn, err := db.Conn(context.Background())
+//	if err != nil {
+//		// handle error from acquiring connection from DB pool
+//	}
+//
+//	err = conn.Raw(func(driverConn interface{}) error {
+//		conn := driverConn.(*stdlib.Conn).Conn() // conn is a *pgx.Conn
+//		// Do pgx specific stuff with conn
+//		conn.CopyFrom(...)
+//		return nil
+//	})
+//	if err != nil {
+//		// handle error that occurred while using *pgx.Conn
+//	}
+package stdlib
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"math/rand"
+	"reflect"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/jackc/pgconn"
+	"github.com/jackc/pgtype"
+	"github.com/jackc/pgx/v4"
+)
+
+// Only intrinsic types should be binary format with database/sql.
+var databaseSQLResultFormats pgx.QueryResultFormatsByOID
+
+var pgxDriver *Driver
+
+type ctxKey int
+
+var ctxKeyFakeTx ctxKey = 0
+
+var ErrNotPgx = errors.New("not pgx *sql.DB")
+
+func init() {
+	pgxDriver = &Driver{
+		configs: make(map[string]*pgx.ConnConfig),
+	}
+	fakeTxConns = make(map[*pgx.Conn]*sql.Tx)
+	sql.Register("pgx", pgxDriver)
+
+	databaseSQLResultFormats = pgx.QueryResultFormatsByOID{
+		pgtype.BoolOID:        1,
+		pgtype.ByteaOID:       1,
+		pgtype.CIDOID:         1,
+		pgtype.DateOID:        1,
+		pgtype.Float4OID:      1,
+		pgtype.Float8OID:      1,
+		pgtype.Int2OID:        1,
+		pgtype.Int4OID:        1,
+		pgtype.Int8OID:        1,
+		pgtype.OIDOID:         1,
+		pgtype.TimestampOID:   1,
+		pgtype.TimestamptzOID: 1,
+		pgtype.XIDOID:         1,
+	}
+}
+
+var (
+	fakeTxMutex sync.Mutex
+	fakeTxConns map[*pgx.Conn]*sql.Tx
+)
+
+// OptionOpenDB options for configuring the driver when opening a new db pool.
+type OptionOpenDB func(*connector)
+
+// OptionBeforeConnect provides a callback for before connect. It is passed a shallow copy of the ConnConfig that will
+// be used to connect, so only its immediate members should be modified.
+func OptionBeforeConnect(bc func(context.Context, *pgx.ConnConfig) error) OptionOpenDB {
+	return func(dc *connector) {
+		dc.BeforeConnect = bc
+	}
+}
+
+// OptionAfterConnect provides a callback for after connect.
+func OptionAfterConnect(ac func(context.Context, *pgx.Conn) error) OptionOpenDB {
+	return func(dc *connector) {
+		dc.AfterConnect = ac
+	}
+}
+
+// OptionResetSession provides a callback that can be used to add custom logic prior to executing a query on the
+// connection if the connection has been used before.
+// If ResetSessionFunc returns ErrBadConn error the connection will be discarded.
+func OptionResetSession(rs func(context.Context, *pgx.Conn) error) OptionOpenDB {
+	return func(dc *connector) {
+		dc.ResetSession = rs
+	}
+}
+
+// RandomizeHostOrderFunc is a BeforeConnect hook that randomizes the host order in the provided connConfig, so that a
+// new host becomes primary each time. This is useful to distribute connections for multi-master databases like
+// CockroachDB. If you use this you likely should set https://golang.org/pkg/database/sql/#DB.SetConnMaxLifetime as well
+// to ensure that connections are periodically rebalanced across your nodes.
+func RandomizeHostOrderFunc(ctx context.Context, connConfig *pgx.ConnConfig) error {
+	if len(connConfig.Fallbacks) == 0 {
+		return nil
+	}
+
+	newFallbacks := append([]*pgconn.FallbackConfig{&pgconn.FallbackConfig{
+		Host:      connConfig.Host,
+		Port:      connConfig.Port,
+		TLSConfig: connConfig.TLSConfig,
+	}}, connConfig.Fallbacks...)
+
+	rand.Shuffle(len(newFallbacks), func(i, j int) {
+		newFallbacks[i], newFallbacks[j] = newFallbacks[j], newFallbacks[i]
+	})
+
+	// Use the one that sorted last as the primary and keep the rest as the fallbacks
+	newPrimary := newFallbacks[len(newFallbacks)-1]
+	connConfig.Host = newPrimary.Host
+	connConfig.Port = newPrimary.Port
+	connConfig.TLSConfig = newPrimary.TLSConfig
+	connConfig.Fallbacks = newFallbacks[:len(newFallbacks)-1]
+	return nil
+}
+
+func OpenDB(config pgx.ConnConfig, opts ...OptionOpenDB) *sql.DB {
+	c := connector{
+		ConnConfig:    config,
+		BeforeConnect: func(context.Context, *pgx.ConnConfig) error { return nil }, // noop before connect by default
+		AfterConnect:  func(context.Context, *pgx.Conn) error { return nil },       // noop after connect by default
+		ResetSession:  func(context.Context, *pgx.Conn) error { return nil },       // noop reset session by default
+		driver:        pgxDriver,
+	}
+
+	for _, opt := range opts {
+		opt(&c)
+	}
+
+	return sql.OpenDB(c)
+}
+
+type connector struct {
+	pgx.ConnConfig
+	BeforeConnect func(context.Context, *pgx.ConnConfig) error // function to call before creation of every new connection
+	AfterConnect  func(context.Context, *pgx.Conn) error       // function to call after creation of every new connection
+	ResetSession  func(context.Context, *pgx.Conn) error       // function is called before a connection is reused
+	driver        *Driver
+}
+
+// Connect implement driver.Connector interface
+func (c connector) Connect(ctx context.Context) (driver.Conn, error) {
+	var (
+		err  error
+		conn *pgx.Conn
+	)
+
+	// Create a shallow copy of the config, so that BeforeConnect can safely modify it
+	connConfig := c.ConnConfig
+	if err = c.BeforeConnect(ctx, &connConfig); err != nil {
+		return nil, err
+	}
+
+	if conn, err = pgx.ConnectConfig(ctx, &connConfig); err != nil {
+		return nil, err
+	}
+
+	if err = c.AfterConnect(ctx, conn); err != nil {
+		return nil, err
+	}
+
+	return &Conn{conn: conn, driver: c.driver, connConfig: connConfig, resetSessionFunc: c.ResetSession}, nil
+}
+
+// Driver implement driver.Connector interface
+func (c connector) Driver() driver.Driver {
+	return c.driver
+}
+
+// GetDefaultDriver returns the driver initialized in the init function
+// and used when the pgx driver is registered.
+func GetDefaultDriver() driver.Driver {
+	return pgxDriver
+}
+
+type Driver struct {
+	configMutex sync.Mutex
+	configs     map[string]*pgx.ConnConfig
+	sequence    int
+}
+
+func (d *Driver) Open(name string) (driver.Conn, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second) // Ensure eventual timeout
+	defer cancel()
+
+	connector, err := d.OpenConnector(name)
+	if err != nil {
+		return nil, err
+	}
+	return connector.Connect(ctx)
+}
+
+func (d *Driver) OpenConnector(name string) (driver.Connector, error) {
+	return &driverConnector{driver: d, name: name}, nil
+}
+
+func (d *Driver) registerConnConfig(c *pgx.ConnConfig) string {
+	d.configMutex.Lock()
+	connStr := fmt.Sprintf("registeredConnConfig%d", d.sequence)
+	d.sequence++
+	d.configs[connStr] = c
+	d.configMutex.Unlock()
+	return connStr
+}
+
+func (d *Driver) unregisterConnConfig(connStr string) {
+	d.configMutex.Lock()
+	delete(d.configs, connStr)
+	d.configMutex.Unlock()
+}
+
+type driverConnector struct {
+	driver *Driver
+	name   string
+}
+
+func (dc *driverConnector) Connect(ctx context.Context) (driver.Conn, error) {
+	var connConfig *pgx.ConnConfig
+
+	dc.driver.configMutex.Lock()
+	connConfig = dc.driver.configs[dc.name]
+	dc.driver.configMutex.Unlock()
+
+	if connConfig == nil {
+		var err error
+		connConfig, err = pgx.ParseConfig(dc.name)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	conn, err := pgx.ConnectConfig(ctx, connConfig)
+	if err != nil {
+		return nil, err
+	}
+
+	c := &Conn{
+		conn:             conn,
+		driver:           dc.driver,
+		connConfig:       *connConfig,
+		resetSessionFunc: func(context.Context, *pgx.Conn) error { return nil },
+	}
+
+	return c, nil
+}
+
+func (dc *driverConnector) Driver() driver.Driver {
+	return dc.driver
+}
+
+// RegisterConnConfig registers a ConnConfig and returns the connection string to use with Open.
+func RegisterConnConfig(c *pgx.ConnConfig) string {
+	return pgxDriver.registerConnConfig(c)
+}
+
+// UnregisterConnConfig removes the ConnConfig registration for connStr.
+func UnregisterConnConfig(connStr string) {
+	pgxDriver.unregisterConnConfig(connStr)
+}
+
+type Conn struct {
+	conn             *pgx.Conn
+	psCount          int64 // Counter used for creating unique prepared statement names
+	driver           *Driver
+	connConfig       pgx.ConnConfig
+	resetSessionFunc func(context.Context, *pgx.Conn) error // Function is called before a connection is reused
+}
+
+// Conn returns the underlying *pgx.Conn
+func (c *Conn) Conn() *pgx.Conn {
+	return c.conn
+}
+
+func (c *Conn) Prepare(query string) (driver.Stmt, error) {
+	return c.PrepareContext(context.Background(), query)
+}
+
+func (c *Conn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
+	if c.conn.IsClosed() {
+		return nil, driver.ErrBadConn
+	}
+
+	name := fmt.Sprintf("pgx_%d", c.psCount)
+	c.psCount++
+
+	sd, err := c.conn.Prepare(ctx, name, query)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Stmt{sd: sd, conn: c}, nil
+}
+
+func (c *Conn) Close() error {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+	defer cancel()
+	return c.conn.Close(ctx)
+}
+
+func (c *Conn) Begin() (driver.Tx, error) {
+	return c.BeginTx(context.Background(), driver.TxOptions{})
+}
+
+func (c *Conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
+	if c.conn.IsClosed() {
+		return nil, driver.ErrBadConn
+	}
+
+	if pconn, ok := ctx.Value(ctxKeyFakeTx).(**pgx.Conn); ok {
+		*pconn = c.conn
+		return fakeTx{}, nil
+	}
+
+	var pgxOpts pgx.TxOptions
+	switch sql.IsolationLevel(opts.Isolation) {
+	case sql.LevelDefault:
+	case sql.LevelReadUncommitted:
+		pgxOpts.IsoLevel = pgx.ReadUncommitted
+	case sql.LevelReadCommitted:
+		pgxOpts.IsoLevel = pgx.ReadCommitted
+	case sql.LevelRepeatableRead, sql.LevelSnapshot:
+		pgxOpts.IsoLevel = pgx.RepeatableRead
+	case sql.LevelSerializable:
+		pgxOpts.IsoLevel = pgx.Serializable
+	default:
+		return nil, fmt.Errorf("unsupported isolation: %v", opts.Isolation)
+	}
+
+	if opts.ReadOnly {
+		pgxOpts.AccessMode = pgx.ReadOnly
+	}
+
+	tx, err := c.conn.BeginTx(ctx, pgxOpts)
+	if err != nil {
+		return nil, err
+	}
+
+	return wrapTx{ctx: ctx, tx: tx}, nil
+}
+
+func (c *Conn) ExecContext(ctx context.Context, query string, argsV []driver.NamedValue) (driver.Result, error) {
+	if c.conn.IsClosed() {
+		return nil, driver.ErrBadConn
+	}
+
+	args := namedValueToInterface(argsV)
+
+	commandTag, err := c.conn.Exec(ctx, query, args...)
+	// if we got a network error before we had a chance to send the query, retry
+	if err != nil {
+		if pgconn.SafeToRetry(err) {
+			return nil, driver.ErrBadConn
+		}
+	}
+	return driver.RowsAffected(commandTag.RowsAffected()), err
+}
+
+func (c *Conn) QueryContext(ctx context.Context, query string, argsV []driver.NamedValue) (driver.Rows, error) {
+	if c.conn.IsClosed() {
+		return nil, driver.ErrBadConn
+	}
+
+	args := []interface{}{databaseSQLResultFormats}
+	args = append(args, namedValueToInterface(argsV)...)
+
+	rows, err := c.conn.Query(ctx, query, args...)
+	if err != nil {
+		if pgconn.SafeToRetry(err) {
+			return nil, driver.ErrBadConn
+		}
+		return nil, err
+	}
+
+	// Preload first row because otherwise we won't know what columns are available when database/sql asks.
+	more := rows.Next()
+	if err = rows.Err(); err != nil {
+		rows.Close()
+		return nil, err
+	}
+	return &Rows{conn: c, rows: rows, skipNext: true, skipNextMore: more}, nil
+}
+
+func (c *Conn) Ping(ctx context.Context) error {
+	if c.conn.IsClosed() {
+		return driver.ErrBadConn
+	}
+
+	err := c.conn.Ping(ctx)
+	if err != nil {
+		// A Ping failure implies some sort of fatal state. The connection is almost certainly already closed by the
+		// failure, but manually close it just to be sure.
+		c.Close()
+		return driver.ErrBadConn
+	}
+
+	return nil
+}
+
+func (c *Conn) CheckNamedValue(*driver.NamedValue) error {
+	// Underlying pgx supports sql.Scanner and driver.Valuer interfaces natively. So everything can be passed through directly.
+	return nil
+}
+
+func (c *Conn) ResetSession(ctx context.Context) error {
+	if c.conn.IsClosed() {
+		return driver.ErrBadConn
+	}
+
+	return c.resetSessionFunc(ctx, c.conn)
+}
+
+type Stmt struct {
+	sd   *pgconn.StatementDescription
+	conn *Conn
+}
+
+func (s *Stmt) Close() error {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+	defer cancel()
+	return s.conn.conn.Deallocate(ctx, s.sd.Name)
+}
+
+func (s *Stmt) NumInput() int {
+	return len(s.sd.ParamOIDs)
+}
+
+func (s *Stmt) Exec(argsV []driver.Value) (driver.Result, error) {
+	return nil, errors.New("Stmt.Exec deprecated and not implemented")
+}
+
+func (s *Stmt) ExecContext(ctx context.Context, argsV []driver.NamedValue) (driver.Result, error) {
+	return s.conn.ExecContext(ctx, s.sd.Name, argsV)
+}
+
+func (s *Stmt) Query(argsV []driver.Value) (driver.Rows, error) {
+	return nil, errors.New("Stmt.Query deprecated and not implemented")
+}
+
+func (s *Stmt) QueryContext(ctx context.Context, argsV []driver.NamedValue) (driver.Rows, error) {
+	return s.conn.QueryContext(ctx, s.sd.Name, argsV)
+}
+
+type rowValueFunc func(src []byte) (driver.Value, error)
+
+type Rows struct {
+	conn         *Conn
+	rows         pgx.Rows
+	valueFuncs   []rowValueFunc
+	skipNext     bool
+	skipNextMore bool
+
+	columnNames []string
+}
+
+func (r *Rows) Columns() []string {
+	if r.columnNames == nil {
+		fields := r.rows.FieldDescriptions()
+		r.columnNames = make([]string, len(fields))
+		for i, fd := range fields {
+			r.columnNames[i] = string(fd.Name)
+		}
+	}
+
+	return r.columnNames
+}
+
+// ColumnTypeDatabaseTypeName returns the database system type name. If the name is unknown the OID is returned.
+func (r *Rows) ColumnTypeDatabaseTypeName(index int) string {
+	if dt, ok := r.conn.conn.ConnInfo().DataTypeForOID(r.rows.FieldDescriptions()[index].DataTypeOID); ok {
+		return strings.ToUpper(dt.Name)
+	}
+
+	return strconv.FormatInt(int64(r.rows.FieldDescriptions()[index].DataTypeOID), 10)
+}
+
+const varHeaderSize = 4
+
+// ColumnTypeLength returns the length of the column type if the column is a
+// variable length type. If the column is not a variable length type ok
+// should return false.
+func (r *Rows) ColumnTypeLength(index int) (int64, bool) {
+	fd := r.rows.FieldDescriptions()[index]
+
+	switch fd.DataTypeOID {
+	case pgtype.TextOID, pgtype.ByteaOID:
+		return math.MaxInt64, true
+	case pgtype.VarcharOID, pgtype.BPCharArrayOID:
+		return int64(fd.TypeModifier - varHeaderSize), true
+	default:
+		return 0, false
+	}
+}
+
+// ColumnTypePrecisionScale should return the precision and scale for decimal
+// types. If not applicable, ok should be false.
+func (r *Rows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool) {
+	fd := r.rows.FieldDescriptions()[index]
+
+	switch fd.DataTypeOID {
+	case pgtype.NumericOID:
+		mod := fd.TypeModifier - varHeaderSize
+		precision = int64((mod >> 16) & 0xffff)
+		scale = int64(mod & 0xffff)
+		return precision, scale, true
+	default:
+		return 0, 0, false
+	}
+}
+
+// ColumnTypeScanType returns the value type that can be used to scan types into.
+func (r *Rows) ColumnTypeScanType(index int) reflect.Type {
+	fd := r.rows.FieldDescriptions()[index]
+
+	switch fd.DataTypeOID {
+	case pgtype.Float8OID:
+		return reflect.TypeOf(float64(0))
+	case pgtype.Float4OID:
+		return reflect.TypeOf(float32(0))
+	case pgtype.Int8OID:
+		return reflect.TypeOf(int64(0))
+	case pgtype.Int4OID:
+		return reflect.TypeOf(int32(0))
+	case pgtype.Int2OID:
+		return reflect.TypeOf(int16(0))
+	case pgtype.BoolOID:
+		return reflect.TypeOf(false)
+	case pgtype.NumericOID:
+		return reflect.TypeOf(float64(0))
+	case pgtype.DateOID, pgtype.TimestampOID, pgtype.TimestamptzOID:
+		return reflect.TypeOf(time.Time{})
+	case pgtype.ByteaOID:
+		return reflect.TypeOf([]byte(nil))
+	default:
+		return reflect.TypeOf("")
+	}
+}
+
+func (r *Rows) Close() error {
+	r.rows.Close()
+	return r.rows.Err()
+}
+
+func (r *Rows) Next(dest []driver.Value) error {
+	ci := r.conn.conn.ConnInfo()
+	fieldDescriptions := r.rows.FieldDescriptions()
+
+	if r.valueFuncs == nil {
+		r.valueFuncs = make([]rowValueFunc, len(fieldDescriptions))
+
+		for i, fd := range fieldDescriptions {
+			dataTypeOID := fd.DataTypeOID
+			format := fd.Format
+
+			switch fd.DataTypeOID {
+			case pgtype.BoolOID:
+				var d bool
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return d, err
+				}
+			case pgtype.ByteaOID:
+				var d []byte
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return d, err
+				}
+			case pgtype.CIDOID:
+				var d pgtype.CID
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.DateOID:
+				var d pgtype.Date
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.Float4OID:
+				var d float32
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return float64(d), err
+				}
+			case pgtype.Float8OID:
+				var d float64
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return d, err
+				}
+			case pgtype.Int2OID:
+				var d int16
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return int64(d), err
+				}
+			case pgtype.Int4OID:
+				var d int32
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return int64(d), err
+				}
+			case pgtype.Int8OID:
+				var d int64
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return d, err
+				}
+			case pgtype.JSONOID:
+				var d pgtype.JSON
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.JSONBOID:
+				var d pgtype.JSONB
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.OIDOID:
+				var d pgtype.OIDValue
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.TimestampOID:
+				var d pgtype.Timestamp
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.TimestamptzOID:
+				var d pgtype.Timestamptz
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			case pgtype.XIDOID:
+				var d pgtype.XID
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					if err != nil {
+						return nil, err
+					}
+					return d.Value()
+				}
+			default:
+				var d string
+				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
+				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
+					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					return d, err
+				}
+			}
+		}
+	}
+
+	var more bool
+	if r.skipNext {
+		more = r.skipNextMore
+		r.skipNext = false
+	} else {
+		more = r.rows.Next()
+	}
+
+	if !more {
+		if r.rows.Err() == nil {
+			return io.EOF
+		} else {
+			return r.rows.Err()
+		}
+	}
+
+	for i, rv := range r.rows.RawValues() {
+		if rv != nil {
+			var err error
+			dest[i], err = r.valueFuncs[i](rv)
+			if err != nil {
+				return fmt.Errorf("convert field %d failed: %v", i, err)
+			}
+		} else {
+			dest[i] = nil
+		}
+	}
+
+	return nil
+}
+
+func valueToInterface(argsV []driver.Value) []interface{} {
+	args := make([]interface{}, 0, len(argsV))
+	for _, v := range argsV {
+		if v != nil {
+			args = append(args, v.(interface{}))
+		} else {
+			args = append(args, nil)
+		}
+	}
+	return args
+}
+
+func namedValueToInterface(argsV []driver.NamedValue) []interface{} {
+	args := make([]interface{}, 0, len(argsV))
+	for _, v := range argsV {
+		if v.Value != nil {
+			args = append(args, v.Value.(interface{}))
+		} else {
+			args = append(args, nil)
+		}
+	}
+	return args
+}
+
+type wrapTx struct {
+	ctx context.Context
+	tx  pgx.Tx
+}
+
+func (wtx wrapTx) Commit() error { return wtx.tx.Commit(wtx.ctx) }
+
+func (wtx wrapTx) Rollback() error { return wtx.tx.Rollback(wtx.ctx) }
+
+type fakeTx struct{}
+
+func (fakeTx) Commit() error { return nil }
+
+func (fakeTx) Rollback() error { return nil }
+
+// AcquireConn acquires a *pgx.Conn from database/sql connection pool. It must be released with ReleaseConn.
+//
+// In Go 1.13 this functionality has been incorporated into the standard library in the db.Conn.Raw() method.
+func AcquireConn(db *sql.DB) (*pgx.Conn, error) {
+	var conn *pgx.Conn
+	ctx := context.WithValue(context.Background(), ctxKeyFakeTx, &conn)
+	tx, err := db.BeginTx(ctx, nil)
+	if err != nil {
+		return nil, err
+	}
+	if conn == nil {
+		tx.Rollback()
+		return nil, ErrNotPgx
+	}
+
+	fakeTxMutex.Lock()
+	fakeTxConns[conn] = tx
+	fakeTxMutex.Unlock()
+
+	return conn, nil
+}
+
+// ReleaseConn releases a *pgx.Conn acquired with AcquireConn.
+func ReleaseConn(db *sql.DB, conn *pgx.Conn) error {
+	var tx *sql.Tx
+	var ok bool
+
+	if conn.PgConn().IsBusy() || conn.PgConn().TxStatus() != 'I' {
+		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+		defer cancel()
+		conn.Close(ctx)
+	}
+
+	fakeTxMutex.Lock()
+	tx, ok = fakeTxConns[conn]
+	if ok {
+		delete(fakeTxConns, conn)
+		fakeTxMutex.Unlock()
+	} else {
+		fakeTxMutex.Unlock()
+		return fmt.Errorf("can't release conn that is not acquired")
+	}
+
+	return tx.Rollback()
+}