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-rw-r--r--vendor/github.com/jackc/pgx/v5/conn.go1395
1 files changed, 1395 insertions, 0 deletions
diff --git a/vendor/github.com/jackc/pgx/v5/conn.go b/vendor/github.com/jackc/pgx/v5/conn.go
new file mode 100644
index 0000000..3117214
--- /dev/null
+++ b/vendor/github.com/jackc/pgx/v5/conn.go
@@ -0,0 +1,1395 @@
+package pgx
+
+import (
+ "context"
+ "crypto/sha256"
+ "encoding/hex"
+ "errors"
+ "fmt"
+ "strconv"
+ "strings"
+ "time"
+
+ "github.com/jackc/pgx/v5/internal/sanitize"
+ "github.com/jackc/pgx/v5/internal/stmtcache"
+ "github.com/jackc/pgx/v5/pgconn"
+ "github.com/jackc/pgx/v5/pgtype"
+)
+
+// 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.
+type ConnConfig struct {
+ pgconn.Config
+
+ Tracer QueryTracer
+
+ // Original connection string that was parsed into config.
+ connString string
+
+ // StatementCacheCapacity is maximum size of the statement cache used when executing a query with "cache_statement"
+ // query exec mode.
+ StatementCacheCapacity int
+
+ // DescriptionCacheCapacity is the maximum size of the description cache used when executing a query with
+ // "cache_describe" query exec mode.
+ DescriptionCacheCapacity int
+
+ // DefaultQueryExecMode controls the default mode for executing queries. By default pgx uses the extended protocol
+ // and automatically prepares and caches prepared statements. However, this may be incompatible with proxies such as
+ // PGBouncer. In this case it may be preferable to use QueryExecModeExec or QueryExecModeSimpleProtocol. The same
+ // functionality can be controlled on a per query basis by passing a QueryExecMode as the first query argument.
+ DefaultQueryExecMode QueryExecMode
+
+ createdByParseConfig bool // Used to enforce created by ParseConfig rule.
+}
+
+// ParseConfigOptions contains options that control how a config is built such as getsslpassword.
+type ParseConfigOptions struct {
+ pgconn.ParseConfigOptions
+}
+
+// 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.
+func (cc *ConnConfig) Copy() *ConnConfig {
+ newConfig := new(ConnConfig)
+ *newConfig = *cc
+ newConfig.Config = *newConfig.Config.Copy()
+ return newConfig
+}
+
+// ConnString returns the connection string as parsed by pgx.ParseConfig into pgx.ConnConfig.
+func (cc *ConnConfig) ConnString() string { return cc.connString }
+
+// 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.
+type Conn struct {
+ pgConn *pgconn.PgConn
+ config *ConnConfig // config used when establishing this connection
+ preparedStatements map[string]*pgconn.StatementDescription
+ statementCache stmtcache.Cache
+ descriptionCache stmtcache.Cache
+
+ queryTracer QueryTracer
+ batchTracer BatchTracer
+ copyFromTracer CopyFromTracer
+ prepareTracer PrepareTracer
+
+ notifications []*pgconn.Notification
+
+ doneChan chan struct{}
+ closedChan chan error
+
+ typeMap *pgtype.Map
+
+ wbuf []byte
+ eqb ExtendedQueryBuilder
+}
+
+// Identifier a PostgreSQL identifier or name. Identifiers can be composed of
+// multiple parts such as ["schema", "table"] or ["table", "column"].
+type Identifier []string
+
+// Sanitize returns a sanitized string safe for SQL interpolation.
+func (ident Identifier) Sanitize() string {
+ parts := make([]string, len(ident))
+ for i := range ident {
+ s := strings.ReplaceAll(ident[i], string([]byte{0}), "")
+ parts[i] = `"` + strings.ReplaceAll(s, `"`, `""`) + `"`
+ }
+ return strings.Join(parts, ".")
+}
+
+var (
+ // ErrNoRows occurs when rows are expected but none are returned.
+ ErrNoRows = errors.New("no rows in result set")
+ // ErrTooManyRows occurs when more rows than expected are returned.
+ ErrTooManyRows = errors.New("too many rows in result set")
+)
+
+var errDisabledStatementCache = fmt.Errorf("cannot use QueryExecModeCacheStatement with disabled statement cache")
+var errDisabledDescriptionCache = fmt.Errorf("cannot use QueryExecModeCacheDescribe with disabled description cache")
+
+// Connect establishes a connection with a PostgreSQL server with a connection string. See
+// pgconn.Connect for details.
+func Connect(ctx context.Context, connString string) (*Conn, error) {
+ connConfig, err := ParseConfig(connString)
+ if err != nil {
+ return nil, err
+ }
+ return connect(ctx, connConfig)
+}
+
+// ConnectWithOptions behaves exactly like Connect with the addition of options. At the present options is only used to
+// provide a GetSSLPassword function.
+func ConnectWithOptions(ctx context.Context, connString string, options ParseConfigOptions) (*Conn, error) {
+ connConfig, err := ParseConfigWithOptions(connString, options)
+ if err != nil {
+ return nil, err
+ }
+ return connect(ctx, connConfig)
+}
+
+// ConnectConfig establishes a connection with a PostgreSQL server with a configuration struct.
+// connConfig must have been created by ParseConfig.
+func ConnectConfig(ctx context.Context, connConfig *ConnConfig) (*Conn, error) {
+ // In general this improves safety. In particular avoid the config.Config.OnNotification mutation from affecting other
+ // connections with the same config. See https://github.com/jackc/pgx/issues/618.
+ connConfig = connConfig.Copy()
+
+ return connect(ctx, connConfig)
+}
+
+// ParseConfigWithOptions behaves exactly as ParseConfig does with the addition of options. At the present options is
+// only used to provide a GetSSLPassword function.
+func ParseConfigWithOptions(connString string, options ParseConfigOptions) (*ConnConfig, error) {
+ config, err := pgconn.ParseConfigWithOptions(connString, options.ParseConfigOptions)
+ if err != nil {
+ return nil, err
+ }
+
+ statementCacheCapacity := 512
+ if s, ok := config.RuntimeParams["statement_cache_capacity"]; ok {
+ delete(config.RuntimeParams, "statement_cache_capacity")
+ n, err := strconv.ParseInt(s, 10, 32)
+ if err != nil {
+ return nil, fmt.Errorf("cannot parse statement_cache_capacity: %w", err)
+ }
+ statementCacheCapacity = int(n)
+ }
+
+ descriptionCacheCapacity := 512
+ if s, ok := config.RuntimeParams["description_cache_capacity"]; ok {
+ delete(config.RuntimeParams, "description_cache_capacity")
+ n, err := strconv.ParseInt(s, 10, 32)
+ if err != nil {
+ return nil, fmt.Errorf("cannot parse description_cache_capacity: %w", err)
+ }
+ descriptionCacheCapacity = int(n)
+ }
+
+ defaultQueryExecMode := QueryExecModeCacheStatement
+ if s, ok := config.RuntimeParams["default_query_exec_mode"]; ok {
+ delete(config.RuntimeParams, "default_query_exec_mode")
+ switch s {
+ case "cache_statement":
+ defaultQueryExecMode = QueryExecModeCacheStatement
+ case "cache_describe":
+ defaultQueryExecMode = QueryExecModeCacheDescribe
+ case "describe_exec":
+ defaultQueryExecMode = QueryExecModeDescribeExec
+ case "exec":
+ defaultQueryExecMode = QueryExecModeExec
+ case "simple_protocol":
+ defaultQueryExecMode = QueryExecModeSimpleProtocol
+ default:
+ return nil, fmt.Errorf("invalid default_query_exec_mode: %s", s)
+ }
+ }
+
+ connConfig := &ConnConfig{
+ Config: *config,
+ createdByParseConfig: true,
+ StatementCacheCapacity: statementCacheCapacity,
+ DescriptionCacheCapacity: descriptionCacheCapacity,
+ DefaultQueryExecMode: defaultQueryExecMode,
+ connString: connString,
+ }
+
+ return connConfig, nil
+}
+
+// ParseConfig creates a ConnConfig from a connection string. ParseConfig handles all options that [pgconn.ParseConfig]
+// does. In addition, it accepts the following options:
+//
+// - default_query_exec_mode.
+// Possible values: "cache_statement", "cache_describe", "describe_exec", "exec", and "simple_protocol". See
+// QueryExecMode constant documentation for the meaning of these values. Default: "cache_statement".
+//
+// - statement_cache_capacity.
+// The maximum size of the statement cache used when executing a query with "cache_statement" query exec mode.
+// Default: 512.
+//
+// - description_cache_capacity.
+// The maximum size of the description cache used when executing a query with "cache_describe" query exec mode.
+// Default: 512.
+func ParseConfig(connString string) (*ConnConfig, error) {
+ return ParseConfigWithOptions(connString, ParseConfigOptions{})
+}
+
+// connect connects to a database. connect takes ownership of config. The caller must not use or access it again.
+func connect(ctx context.Context, config *ConnConfig) (c *Conn, err error) {
+ if connectTracer, ok := config.Tracer.(ConnectTracer); ok {
+ ctx = connectTracer.TraceConnectStart(ctx, TraceConnectStartData{ConnConfig: config})
+ defer func() {
+ connectTracer.TraceConnectEnd(ctx, TraceConnectEndData{Conn: c, Err: err})
+ }()
+ }
+
+ // Default values are set in ParseConfig. Enforce initial creation by ParseConfig rather than setting defaults from
+ // zero values.
+ if !config.createdByParseConfig {
+ panic("config must be created by ParseConfig")
+ }
+
+ c = &Conn{
+ config: config,
+ typeMap: pgtype.NewMap(),
+ queryTracer: config.Tracer,
+ }
+
+ if t, ok := c.queryTracer.(BatchTracer); ok {
+ c.batchTracer = t
+ }
+ if t, ok := c.queryTracer.(CopyFromTracer); ok {
+ c.copyFromTracer = t
+ }
+ if t, ok := c.queryTracer.(PrepareTracer); ok {
+ c.prepareTracer = t
+ }
+
+ // Only install pgx notification system if no other callback handler is present.
+ if config.Config.OnNotification == nil {
+ config.Config.OnNotification = c.bufferNotifications
+ }
+
+ c.pgConn, err = pgconn.ConnectConfig(ctx, &config.Config)
+ if err != nil {
+ return nil, err
+ }
+
+ c.preparedStatements = make(map[string]*pgconn.StatementDescription)
+ c.doneChan = make(chan struct{})
+ c.closedChan = make(chan error)
+ c.wbuf = make([]byte, 0, 1024)
+
+ if c.config.StatementCacheCapacity > 0 {
+ c.statementCache = stmtcache.NewLRUCache(c.config.StatementCacheCapacity)
+ }
+
+ if c.config.DescriptionCacheCapacity > 0 {
+ c.descriptionCache = stmtcache.NewLRUCache(c.config.DescriptionCacheCapacity)
+ }
+
+ return c, nil
+}
+
+// Close closes a connection. It is safe to call Close on an already closed
+// connection.
+func (c *Conn) Close(ctx context.Context) error {
+ if c.IsClosed() {
+ return nil
+ }
+
+ err := c.pgConn.Close(ctx)
+ return err
+}
+
+// Prepare creates a prepared statement with name and sql. sql can contain placeholders for bound parameters. These
+// placeholders are referenced positionally as $1, $2, etc. name can be used instead of sql with Query, QueryRow, and
+// Exec to execute the statement. It can also be used with Batch.Queue.
+//
+// The underlying PostgreSQL identifier for the prepared statement will be name if name != sql or a digest of sql if
+// name == sql.
+//
+// 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 (c *Conn) Prepare(ctx context.Context, name, sql string) (sd *pgconn.StatementDescription, err error) {
+ if c.prepareTracer != nil {
+ ctx = c.prepareTracer.TracePrepareStart(ctx, c, TracePrepareStartData{Name: name, SQL: sql})
+ }
+
+ if name != "" {
+ var ok bool
+ if sd, ok = c.preparedStatements[name]; ok && sd.SQL == sql {
+ if c.prepareTracer != nil {
+ c.prepareTracer.TracePrepareEnd(ctx, c, TracePrepareEndData{AlreadyPrepared: true})
+ }
+ return sd, nil
+ }
+ }
+
+ if c.prepareTracer != nil {
+ defer func() {
+ c.prepareTracer.TracePrepareEnd(ctx, c, TracePrepareEndData{Err: err})
+ }()
+ }
+
+ var psName, psKey string
+ if name == sql {
+ digest := sha256.Sum256([]byte(sql))
+ psName = "stmt_" + hex.EncodeToString(digest[0:24])
+ psKey = sql
+ } else {
+ psName = name
+ psKey = name
+ }
+
+ sd, err = c.pgConn.Prepare(ctx, psName, sql, nil)
+ if err != nil {
+ return nil, err
+ }
+
+ if psKey != "" {
+ c.preparedStatements[psKey] = sd
+ }
+
+ return sd, nil
+}
+
+// Deallocate releases a prepared statement. Calling Deallocate on a non-existent prepared statement will succeed.
+func (c *Conn) Deallocate(ctx context.Context, name string) error {
+ var psName string
+ sd := c.preparedStatements[name]
+ if sd != nil {
+ psName = sd.Name
+ } else {
+ psName = name
+ }
+
+ err := c.pgConn.Deallocate(ctx, psName)
+ if err != nil {
+ return err
+ }
+
+ if sd != nil {
+ delete(c.preparedStatements, name)
+ }
+
+ return nil
+}
+
+// DeallocateAll releases all previously prepared statements from the server and client, where it also resets the statement and description cache.
+func (c *Conn) DeallocateAll(ctx context.Context) error {
+ c.preparedStatements = map[string]*pgconn.StatementDescription{}
+ if c.config.StatementCacheCapacity > 0 {
+ c.statementCache = stmtcache.NewLRUCache(c.config.StatementCacheCapacity)
+ }
+ if c.config.DescriptionCacheCapacity > 0 {
+ c.descriptionCache = stmtcache.NewLRUCache(c.config.DescriptionCacheCapacity)
+ }
+ _, err := c.pgConn.Exec(ctx, "deallocate all").ReadAll()
+ return err
+}
+
+func (c *Conn) bufferNotifications(_ *pgconn.PgConn, n *pgconn.Notification) {
+ c.notifications = append(c.notifications, n)
+}
+
+// WaitForNotification waits for a PostgreSQL notification. It wraps the underlying pgconn notification system in a
+// slightly more convenient form.
+func (c *Conn) WaitForNotification(ctx context.Context) (*pgconn.Notification, error) {
+ var n *pgconn.Notification
+
+ // Return already received notification immediately
+ if len(c.notifications) > 0 {
+ n = c.notifications[0]
+ c.notifications = c.notifications[1:]
+ return n, nil
+ }
+
+ err := c.pgConn.WaitForNotification(ctx)
+ if len(c.notifications) > 0 {
+ n = c.notifications[0]
+ c.notifications = c.notifications[1:]
+ }
+ return n, err
+}
+
+// IsClosed reports if the connection has been closed.
+func (c *Conn) IsClosed() bool {
+ return c.pgConn.IsClosed()
+}
+
+func (c *Conn) die(err error) {
+ if c.IsClosed() {
+ return
+ }
+
+ ctx, cancel := context.WithCancel(context.Background())
+ cancel() // force immediate hard cancel
+ c.pgConn.Close(ctx)
+}
+
+func quoteIdentifier(s string) string {
+ return `"` + strings.ReplaceAll(s, `"`, `""`) + `"`
+}
+
+// Ping delegates to the underlying *pgconn.PgConn.Ping.
+func (c *Conn) Ping(ctx context.Context) error {
+ return c.pgConn.Ping(ctx)
+}
+
+// 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 (c *Conn) PgConn() *pgconn.PgConn { return c.pgConn }
+
+// TypeMap returns the connection info used for this connection.
+func (c *Conn) TypeMap() *pgtype.Map { return c.typeMap }
+
+// Config returns a copy of config that was used to establish this connection.
+func (c *Conn) Config() *ConnConfig { return c.config.Copy() }
+
+// 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 (c *Conn) Exec(ctx context.Context, sql string, arguments ...any) (pgconn.CommandTag, error) {
+ if c.queryTracer != nil {
+ ctx = c.queryTracer.TraceQueryStart(ctx, c, TraceQueryStartData{SQL: sql, Args: arguments})
+ }
+
+ if err := c.deallocateInvalidatedCachedStatements(ctx); err != nil {
+ return pgconn.CommandTag{}, err
+ }
+
+ commandTag, err := c.exec(ctx, sql, arguments...)
+
+ if c.queryTracer != nil {
+ c.queryTracer.TraceQueryEnd(ctx, c, TraceQueryEndData{CommandTag: commandTag, Err: err})
+ }
+
+ return commandTag, err
+}
+
+func (c *Conn) exec(ctx context.Context, sql string, arguments ...any) (commandTag pgconn.CommandTag, err error) {
+ mode := c.config.DefaultQueryExecMode
+ var queryRewriter QueryRewriter
+
+optionLoop:
+ for len(arguments) > 0 {
+ switch arg := arguments[0].(type) {
+ case QueryExecMode:
+ mode = arg
+ arguments = arguments[1:]
+ case QueryRewriter:
+ queryRewriter = arg
+ arguments = arguments[1:]
+ default:
+ break optionLoop
+ }
+ }
+
+ if queryRewriter != nil {
+ sql, arguments, err = queryRewriter.RewriteQuery(ctx, c, sql, arguments)
+ if err != nil {
+ return pgconn.CommandTag{}, fmt.Errorf("rewrite query failed: %w", err)
+ }
+ }
+
+ // Always use simple protocol when there are no arguments.
+ if len(arguments) == 0 {
+ mode = QueryExecModeSimpleProtocol
+ }
+
+ if sd, ok := c.preparedStatements[sql]; ok {
+ return c.execPrepared(ctx, sd, arguments)
+ }
+
+ switch mode {
+ case QueryExecModeCacheStatement:
+ if c.statementCache == nil {
+ return pgconn.CommandTag{}, errDisabledStatementCache
+ }
+ sd := c.statementCache.Get(sql)
+ if sd == nil {
+ sd, err = c.Prepare(ctx, stmtcache.StatementName(sql), sql)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+ c.statementCache.Put(sd)
+ }
+
+ return c.execPrepared(ctx, sd, arguments)
+ case QueryExecModeCacheDescribe:
+ if c.descriptionCache == nil {
+ return pgconn.CommandTag{}, errDisabledDescriptionCache
+ }
+ sd := c.descriptionCache.Get(sql)
+ if sd == nil {
+ sd, err = c.Prepare(ctx, "", sql)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+ c.descriptionCache.Put(sd)
+ }
+
+ return c.execParams(ctx, sd, arguments)
+ case QueryExecModeDescribeExec:
+ sd, err := c.Prepare(ctx, "", sql)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+ return c.execPrepared(ctx, sd, arguments)
+ case QueryExecModeExec:
+ return c.execSQLParams(ctx, sql, arguments)
+ case QueryExecModeSimpleProtocol:
+ return c.execSimpleProtocol(ctx, sql, arguments)
+ default:
+ return pgconn.CommandTag{}, fmt.Errorf("unknown QueryExecMode: %v", mode)
+ }
+}
+
+func (c *Conn) execSimpleProtocol(ctx context.Context, sql string, arguments []any) (commandTag pgconn.CommandTag, err error) {
+ if len(arguments) > 0 {
+ sql, err = c.sanitizeForSimpleQuery(sql, arguments...)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+ }
+
+ mrr := c.pgConn.Exec(ctx, sql)
+ for mrr.NextResult() {
+ commandTag, _ = mrr.ResultReader().Close()
+ }
+ err = mrr.Close()
+ return commandTag, err
+}
+
+func (c *Conn) execParams(ctx context.Context, sd *pgconn.StatementDescription, arguments []any) (pgconn.CommandTag, error) {
+ err := c.eqb.Build(c.typeMap, sd, arguments)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+
+ result := c.pgConn.ExecParams(ctx, sd.SQL, c.eqb.ParamValues, sd.ParamOIDs, c.eqb.ParamFormats, c.eqb.ResultFormats).Read()
+ c.eqb.reset() // Allow c.eqb internal memory to be GC'ed as soon as possible.
+ return result.CommandTag, result.Err
+}
+
+func (c *Conn) execPrepared(ctx context.Context, sd *pgconn.StatementDescription, arguments []any) (pgconn.CommandTag, error) {
+ err := c.eqb.Build(c.typeMap, sd, arguments)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+
+ result := c.pgConn.ExecPrepared(ctx, sd.Name, c.eqb.ParamValues, c.eqb.ParamFormats, c.eqb.ResultFormats).Read()
+ c.eqb.reset() // Allow c.eqb internal memory to be GC'ed as soon as possible.
+ return result.CommandTag, result.Err
+}
+
+type unknownArgumentTypeQueryExecModeExecError struct {
+ arg any
+}
+
+func (e *unknownArgumentTypeQueryExecModeExecError) Error() string {
+ return fmt.Sprintf("cannot use unregistered type %T as query argument in QueryExecModeExec", e.arg)
+}
+
+func (c *Conn) execSQLParams(ctx context.Context, sql string, args []any) (pgconn.CommandTag, error) {
+ err := c.eqb.Build(c.typeMap, nil, args)
+ if err != nil {
+ return pgconn.CommandTag{}, err
+ }
+
+ result := c.pgConn.ExecParams(ctx, sql, c.eqb.ParamValues, nil, c.eqb.ParamFormats, c.eqb.ResultFormats).Read()
+ c.eqb.reset() // Allow c.eqb internal memory to be GC'ed as soon as possible.
+ return result.CommandTag, result.Err
+}
+
+func (c *Conn) getRows(ctx context.Context, sql string, args []any) *baseRows {
+ r := &baseRows{}
+
+ r.ctx = ctx
+ r.queryTracer = c.queryTracer
+ r.typeMap = c.typeMap
+ r.startTime = time.Now()
+ r.sql = sql
+ r.args = args
+ r.conn = c
+
+ return r
+}
+
+type QueryExecMode int32
+
+const (
+ _ QueryExecMode = iota
+
+ // Automatically prepare and cache statements. This uses the extended protocol. Queries are executed in a single round
+ // trip after the statement is cached. This is the default. If the database schema is modified or the search_path is
+ // changed after a statement is cached then the first execution of a previously cached query may fail. e.g. If the
+ // number of columns returned by a "SELECT *" changes or the type of a column is changed.
+ QueryExecModeCacheStatement
+
+ // Cache statement descriptions (i.e. argument and result types) and assume they do not change. This uses the extended
+ // protocol. Queries are executed in a single round trip after the description is cached. If the database schema is
+ // modified or the search_path is changed after a statement is cached then the first execution of a previously cached
+ // query may fail. e.g. If the number of columns returned by a "SELECT *" changes or the type of a column is changed.
+ QueryExecModeCacheDescribe
+
+ // Get the statement description on every execution. This uses the extended protocol. Queries require two round trips
+ // to execute. It does not use named prepared statements. But it does use the unnamed prepared statement to get the
+ // statement description on the first round trip and then uses it to execute the query on the second round trip. This
+ // may cause problems with connection poolers that switch the underlying connection between round trips. It is safe
+ // even when the database schema is modified concurrently.
+ QueryExecModeDescribeExec
+
+ // Assume the PostgreSQL query parameter types based on the Go type of the arguments. This uses the extended protocol
+ // with text formatted parameters and results. Queries are executed in a single round trip. Type mappings can be
+ // registered with pgtype.Map.RegisterDefaultPgType. Queries will be rejected that have arguments that are
+ // unregistered or ambiguous. e.g. A map[string]string may have the PostgreSQL type json or hstore. Modes that know
+ // the PostgreSQL type can use a map[string]string directly as an argument. This mode cannot.
+ QueryExecModeExec
+
+ // Use the simple protocol. Assume the PostgreSQL query parameter types based on the Go type of the arguments.
+ // Queries are executed in a single round trip. Type mappings can be registered with
+ // pgtype.Map.RegisterDefaultPgType. Queries will be rejected that have arguments that are unregistered or ambiguous.
+ // e.g. A map[string]string may have the PostgreSQL type json or hstore. Modes that know the PostgreSQL type can use
+ // a map[string]string directly as an argument. This mode cannot.
+ //
+ // QueryExecModeSimpleProtocol should have the user application visible behavior as QueryExecModeExec with minor
+ // exceptions such as behavior when multiple result returning queries are erroneously sent in a single string.
+ //
+ // QueryExecModeSimpleProtocol uses client side parameter interpolation. All values are quoted and escaped. Prefer
+ // QueryExecModeExec over QueryExecModeSimpleProtocol whenever possible. In general QueryExecModeSimpleProtocol
+ // should only be used if connecting to a proxy server, connection pool server, or non-PostgreSQL server that does
+ // not support the extended protocol.
+ QueryExecModeSimpleProtocol
+)
+
+func (m QueryExecMode) String() string {
+ switch m {
+ case QueryExecModeCacheStatement:
+ return "cache statement"
+ case QueryExecModeCacheDescribe:
+ return "cache describe"
+ case QueryExecModeDescribeExec:
+ return "describe exec"
+ case QueryExecModeExec:
+ return "exec"
+ case QueryExecModeSimpleProtocol:
+ return "simple protocol"
+ default:
+ return "invalid"
+ }
+}
+
+// QueryResultFormats controls the result format (text=0, binary=1) of a query by result column position.
+type QueryResultFormats []int16
+
+// QueryResultFormatsByOID controls the result format (text=0, binary=1) of a query by the result column OID.
+type QueryResultFormatsByOID map[uint32]int16
+
+// QueryRewriter rewrites a query when used as the first arguments to a query method.
+type QueryRewriter interface {
+ RewriteQuery(ctx context.Context, conn *Conn, sql string, args []any) (newSQL string, newArgs []any, err error)
+}
+
+// Query sends a query to the server and returns a Rows to read the results. Only errors encountered sending the query
+// and initializing Rows will be returned. Err() on the returned Rows must be checked after the Rows is closed to
+// determine if the query executed successfully.
+//
+// The returned Rows must be closed before the connection can be used again. It is safe to attempt to read from the
+// returned Rows even if an error is returned. The error will be the available in rows.Err() after rows are closed. It
+// is allowed to ignore the error returned from Query and handle it in Rows.
+//
+// It is possible for a call of FieldDescriptions on the returned Rows to return nil even if the Query call did not
+// return an error.
+//
+// It is possible for a query to return one or more rows before encountering an error. In most cases the rows should be
+// collected before processing rather than processed while receiving each row. This avoids the possibility of the
+// application processing rows from a query that the server rejected. The CollectRows function is useful here.
+//
+// An implementor of QueryRewriter may be passed as the first element of args. It can rewrite the sql and change or
+// replace args. For example, NamedArgs is QueryRewriter that implements named arguments.
+//
+// For extra control over how the query is executed, the types QueryExecMode, 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 (c *Conn) Query(ctx context.Context, sql string, args ...any) (Rows, error) {
+ if c.queryTracer != nil {
+ ctx = c.queryTracer.TraceQueryStart(ctx, c, TraceQueryStartData{SQL: sql, Args: args})
+ }
+
+ if err := c.deallocateInvalidatedCachedStatements(ctx); err != nil {
+ if c.queryTracer != nil {
+ c.queryTracer.TraceQueryEnd(ctx, c, TraceQueryEndData{Err: err})
+ }
+ return &baseRows{err: err, closed: true}, err
+ }
+
+ var resultFormats QueryResultFormats
+ var resultFormatsByOID QueryResultFormatsByOID
+ mode := c.config.DefaultQueryExecMode
+ var queryRewriter QueryRewriter
+
+optionLoop:
+ for len(args) > 0 {
+ switch arg := args[0].(type) {
+ case QueryResultFormats:
+ resultFormats = arg
+ args = args[1:]
+ case QueryResultFormatsByOID:
+ resultFormatsByOID = arg
+ args = args[1:]
+ case QueryExecMode:
+ mode = arg
+ args = args[1:]
+ case QueryRewriter:
+ queryRewriter = arg
+ args = args[1:]
+ default:
+ break optionLoop
+ }
+ }
+
+ if queryRewriter != nil {
+ var err error
+ originalSQL := sql
+ originalArgs := args
+ sql, args, err = queryRewriter.RewriteQuery(ctx, c, sql, args)
+ if err != nil {
+ rows := c.getRows(ctx, originalSQL, originalArgs)
+ err = fmt.Errorf("rewrite query failed: %w", err)
+ rows.fatal(err)
+ return rows, err
+ }
+ }
+
+ // Bypass any statement caching.
+ if sql == "" {
+ mode = QueryExecModeSimpleProtocol
+ }
+
+ c.eqb.reset()
+ rows := c.getRows(ctx, sql, args)
+
+ var err error
+ sd, explicitPreparedStatement := c.preparedStatements[sql]
+ if sd != nil || mode == QueryExecModeCacheStatement || mode == QueryExecModeCacheDescribe || mode == QueryExecModeDescribeExec {
+ if sd == nil {
+ sd, err = c.getStatementDescription(ctx, mode, sql)
+ if err != nil {
+ rows.fatal(err)
+ return rows, err
+ }
+ }
+
+ if len(sd.ParamOIDs) != len(args) {
+ rows.fatal(fmt.Errorf("expected %d arguments, got %d", len(sd.ParamOIDs), len(args)))
+ return rows, rows.err
+ }
+
+ rows.sql = sd.SQL
+
+ err = c.eqb.Build(c.typeMap, sd, args)
+ if err != nil {
+ rows.fatal(err)
+ return rows, rows.err
+ }
+
+ if resultFormatsByOID != nil {
+ resultFormats = make([]int16, len(sd.Fields))
+ for i := range resultFormats {
+ resultFormats[i] = resultFormatsByOID[uint32(sd.Fields[i].DataTypeOID)]
+ }
+ }
+
+ if resultFormats == nil {
+ resultFormats = c.eqb.ResultFormats
+ }
+
+ if !explicitPreparedStatement && mode == QueryExecModeCacheDescribe {
+ rows.resultReader = c.pgConn.ExecParams(ctx, sql, c.eqb.ParamValues, sd.ParamOIDs, c.eqb.ParamFormats, resultFormats)
+ } else {
+ rows.resultReader = c.pgConn.ExecPrepared(ctx, sd.Name, c.eqb.ParamValues, c.eqb.ParamFormats, resultFormats)
+ }
+ } else if mode == QueryExecModeExec {
+ err := c.eqb.Build(c.typeMap, nil, args)
+ if err != nil {
+ rows.fatal(err)
+ return rows, rows.err
+ }
+
+ rows.resultReader = c.pgConn.ExecParams(ctx, sql, c.eqb.ParamValues, nil, c.eqb.ParamFormats, c.eqb.ResultFormats)
+ } else if mode == QueryExecModeSimpleProtocol {
+ sql, err = c.sanitizeForSimpleQuery(sql, args...)
+ if err != nil {
+ rows.fatal(err)
+ return rows, err
+ }
+
+ mrr := c.pgConn.Exec(ctx, sql)
+ if mrr.NextResult() {
+ rows.resultReader = mrr.ResultReader()
+ rows.multiResultReader = mrr
+ } else {
+ err = mrr.Close()
+ rows.fatal(err)
+ return rows, err
+ }
+
+ return rows, nil
+ } else {
+ err = fmt.Errorf("unknown QueryExecMode: %v", mode)
+ rows.fatal(err)
+ return rows, rows.err
+ }
+
+ c.eqb.reset() // Allow c.eqb internal memory to be GC'ed as soon as possible.
+
+ return rows, rows.err
+}
+
+// getStatementDescription returns the statement description of the sql query
+// according to the given mode.
+//
+// If the mode is one that doesn't require to know the param and result OIDs
+// then nil is returned without error.
+func (c *Conn) getStatementDescription(
+ ctx context.Context,
+ mode QueryExecMode,
+ sql string,
+) (sd *pgconn.StatementDescription, err error) {
+
+ switch mode {
+ case QueryExecModeCacheStatement:
+ if c.statementCache == nil {
+ return nil, errDisabledStatementCache
+ }
+ sd = c.statementCache.Get(sql)
+ if sd == nil {
+ sd, err = c.Prepare(ctx, stmtcache.StatementName(sql), sql)
+ if err != nil {
+ return nil, err
+ }
+ c.statementCache.Put(sd)
+ }
+ case QueryExecModeCacheDescribe:
+ if c.descriptionCache == nil {
+ return nil, errDisabledDescriptionCache
+ }
+ sd = c.descriptionCache.Get(sql)
+ if sd == nil {
+ sd, err = c.Prepare(ctx, "", sql)
+ if err != nil {
+ return nil, err
+ }
+ c.descriptionCache.Put(sd)
+ }
+ case QueryExecModeDescribeExec:
+ return c.Prepare(ctx, "", sql)
+ }
+ return sd, err
+}
+
+// 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 (c *Conn) QueryRow(ctx context.Context, sql string, args ...any) Row {
+ rows, _ := c.Query(ctx, sql, args...)
+ return (*connRow)(rows.(*baseRows))
+}
+
+// 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 (c *Conn) SendBatch(ctx context.Context, b *Batch) (br BatchResults) {
+ if c.batchTracer != nil {
+ ctx = c.batchTracer.TraceBatchStart(ctx, c, TraceBatchStartData{Batch: b})
+ defer func() {
+ err := br.(interface{ earlyError() error }).earlyError()
+ if err != nil {
+ c.batchTracer.TraceBatchEnd(ctx, c, TraceBatchEndData{Err: err})
+ }
+ }()
+ }
+
+ if err := c.deallocateInvalidatedCachedStatements(ctx); err != nil {
+ return &batchResults{ctx: ctx, conn: c, err: err}
+ }
+
+ for _, bi := range b.QueuedQueries {
+ var queryRewriter QueryRewriter
+ sql := bi.SQL
+ arguments := bi.Arguments
+
+ optionLoop:
+ for len(arguments) > 0 {
+ // Update Batch.Queue function comment when additional options are implemented
+ switch arg := arguments[0].(type) {
+ case QueryRewriter:
+ queryRewriter = arg
+ arguments = arguments[1:]
+ default:
+ break optionLoop
+ }
+ }
+
+ if queryRewriter != nil {
+ var err error
+ sql, arguments, err = queryRewriter.RewriteQuery(ctx, c, sql, arguments)
+ if err != nil {
+ return &batchResults{ctx: ctx, conn: c, err: fmt.Errorf("rewrite query failed: %w", err)}
+ }
+ }
+
+ bi.SQL = sql
+ bi.Arguments = arguments
+ }
+
+ // TODO: changing mode per batch? Update Batch.Queue function comment when implemented
+ mode := c.config.DefaultQueryExecMode
+ if mode == QueryExecModeSimpleProtocol {
+ return c.sendBatchQueryExecModeSimpleProtocol(ctx, b)
+ }
+
+ // All other modes use extended protocol and thus can use prepared statements.
+ for _, bi := range b.QueuedQueries {
+ if sd, ok := c.preparedStatements[bi.SQL]; ok {
+ bi.sd = sd
+ }
+ }
+
+ switch mode {
+ case QueryExecModeExec:
+ return c.sendBatchQueryExecModeExec(ctx, b)
+ case QueryExecModeCacheStatement:
+ return c.sendBatchQueryExecModeCacheStatement(ctx, b)
+ case QueryExecModeCacheDescribe:
+ return c.sendBatchQueryExecModeCacheDescribe(ctx, b)
+ case QueryExecModeDescribeExec:
+ return c.sendBatchQueryExecModeDescribeExec(ctx, b)
+ default:
+ panic("unknown QueryExecMode")
+ }
+}
+
+func (c *Conn) sendBatchQueryExecModeSimpleProtocol(ctx context.Context, b *Batch) *batchResults {
+ var sb strings.Builder
+ for i, bi := range b.QueuedQueries {
+ if i > 0 {
+ sb.WriteByte(';')
+ }
+ sql, err := c.sanitizeForSimpleQuery(bi.SQL, bi.Arguments...)
+ if err != nil {
+ return &batchResults{ctx: ctx, conn: c, err: err}
+ }
+ sb.WriteString(sql)
+ }
+ mrr := c.pgConn.Exec(ctx, sb.String())
+ return &batchResults{
+ ctx: ctx,
+ conn: c,
+ mrr: mrr,
+ b: b,
+ qqIdx: 0,
+ }
+}
+
+func (c *Conn) sendBatchQueryExecModeExec(ctx context.Context, b *Batch) *batchResults {
+ batch := &pgconn.Batch{}
+
+ for _, bi := range b.QueuedQueries {
+ sd := bi.sd
+ if sd != nil {
+ err := c.eqb.Build(c.typeMap, sd, bi.Arguments)
+ if err != nil {
+ return &batchResults{ctx: ctx, conn: c, err: err}
+ }
+
+ batch.ExecPrepared(sd.Name, c.eqb.ParamValues, c.eqb.ParamFormats, c.eqb.ResultFormats)
+ } else {
+ err := c.eqb.Build(c.typeMap, nil, bi.Arguments)
+ if err != nil {
+ return &batchResults{ctx: ctx, conn: c, err: err}
+ }
+ batch.ExecParams(bi.SQL, c.eqb.ParamValues, nil, c.eqb.ParamFormats, c.eqb.ResultFormats)
+ }
+ }
+
+ c.eqb.reset() // Allow c.eqb internal memory to be GC'ed as soon as possible.
+
+ mrr := c.pgConn.ExecBatch(ctx, batch)
+
+ return &batchResults{
+ ctx: ctx,
+ conn: c,
+ mrr: mrr,
+ b: b,
+ qqIdx: 0,
+ }
+}
+
+func (c *Conn) sendBatchQueryExecModeCacheStatement(ctx context.Context, b *Batch) (pbr *pipelineBatchResults) {
+ if c.statementCache == nil {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: errDisabledStatementCache, closed: true}
+ }
+
+ distinctNewQueries := []*pgconn.StatementDescription{}
+ distinctNewQueriesIdxMap := make(map[string]int)
+
+ for _, bi := range b.QueuedQueries {
+ if bi.sd == nil {
+ sd := c.statementCache.Get(bi.SQL)
+ if sd != nil {
+ bi.sd = sd
+ } else {
+ if idx, present := distinctNewQueriesIdxMap[bi.SQL]; present {
+ bi.sd = distinctNewQueries[idx]
+ } else {
+ sd = &pgconn.StatementDescription{
+ Name: stmtcache.StatementName(bi.SQL),
+ SQL: bi.SQL,
+ }
+ distinctNewQueriesIdxMap[sd.SQL] = len(distinctNewQueries)
+ distinctNewQueries = append(distinctNewQueries, sd)
+ bi.sd = sd
+ }
+ }
+ }
+ }
+
+ return c.sendBatchExtendedWithDescription(ctx, b, distinctNewQueries, c.statementCache)
+}
+
+func (c *Conn) sendBatchQueryExecModeCacheDescribe(ctx context.Context, b *Batch) (pbr *pipelineBatchResults) {
+ if c.descriptionCache == nil {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: errDisabledDescriptionCache, closed: true}
+ }
+
+ distinctNewQueries := []*pgconn.StatementDescription{}
+ distinctNewQueriesIdxMap := make(map[string]int)
+
+ for _, bi := range b.QueuedQueries {
+ if bi.sd == nil {
+ sd := c.descriptionCache.Get(bi.SQL)
+ if sd != nil {
+ bi.sd = sd
+ } else {
+ if idx, present := distinctNewQueriesIdxMap[bi.SQL]; present {
+ bi.sd = distinctNewQueries[idx]
+ } else {
+ sd = &pgconn.StatementDescription{
+ SQL: bi.SQL,
+ }
+ distinctNewQueriesIdxMap[sd.SQL] = len(distinctNewQueries)
+ distinctNewQueries = append(distinctNewQueries, sd)
+ bi.sd = sd
+ }
+ }
+ }
+ }
+
+ return c.sendBatchExtendedWithDescription(ctx, b, distinctNewQueries, c.descriptionCache)
+}
+
+func (c *Conn) sendBatchQueryExecModeDescribeExec(ctx context.Context, b *Batch) (pbr *pipelineBatchResults) {
+ distinctNewQueries := []*pgconn.StatementDescription{}
+ distinctNewQueriesIdxMap := make(map[string]int)
+
+ for _, bi := range b.QueuedQueries {
+ if bi.sd == nil {
+ if idx, present := distinctNewQueriesIdxMap[bi.SQL]; present {
+ bi.sd = distinctNewQueries[idx]
+ } else {
+ sd := &pgconn.StatementDescription{
+ SQL: bi.SQL,
+ }
+ distinctNewQueriesIdxMap[sd.SQL] = len(distinctNewQueries)
+ distinctNewQueries = append(distinctNewQueries, sd)
+ bi.sd = sd
+ }
+ }
+ }
+
+ return c.sendBatchExtendedWithDescription(ctx, b, distinctNewQueries, nil)
+}
+
+func (c *Conn) sendBatchExtendedWithDescription(ctx context.Context, b *Batch, distinctNewQueries []*pgconn.StatementDescription, sdCache stmtcache.Cache) (pbr *pipelineBatchResults) {
+ pipeline := c.pgConn.StartPipeline(ctx)
+ defer func() {
+ if pbr != nil && pbr.err != nil {
+ pipeline.Close()
+ }
+ }()
+
+ // Prepare any needed queries
+ if len(distinctNewQueries) > 0 {
+ for _, sd := range distinctNewQueries {
+ pipeline.SendPrepare(sd.Name, sd.SQL, nil)
+ }
+
+ err := pipeline.Sync()
+ if err != nil {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: err, closed: true}
+ }
+
+ for _, sd := range distinctNewQueries {
+ results, err := pipeline.GetResults()
+ if err != nil {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: err, closed: true}
+ }
+
+ resultSD, ok := results.(*pgconn.StatementDescription)
+ if !ok {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: fmt.Errorf("expected statement description, got %T", results), closed: true}
+ }
+
+ // Fill in the previously empty / pending statement descriptions.
+ sd.ParamOIDs = resultSD.ParamOIDs
+ sd.Fields = resultSD.Fields
+ }
+
+ results, err := pipeline.GetResults()
+ if err != nil {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: err, closed: true}
+ }
+
+ _, ok := results.(*pgconn.PipelineSync)
+ if !ok {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: fmt.Errorf("expected sync, got %T", results), closed: true}
+ }
+ }
+
+ // Put all statements into the cache. It's fine if it overflows because HandleInvalidated will clean them up later.
+ if sdCache != nil {
+ for _, sd := range distinctNewQueries {
+ sdCache.Put(sd)
+ }
+ }
+
+ // Queue the queries.
+ for _, bi := range b.QueuedQueries {
+ err := c.eqb.Build(c.typeMap, bi.sd, bi.Arguments)
+ if err != nil {
+ // we wrap the error so we the user can understand which query failed inside the batch
+ err = fmt.Errorf("error building query %s: %w", bi.SQL, err)
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: err, closed: true}
+ }
+
+ if bi.sd.Name == "" {
+ pipeline.SendQueryParams(bi.sd.SQL, c.eqb.ParamValues, bi.sd.ParamOIDs, c.eqb.ParamFormats, c.eqb.ResultFormats)
+ } else {
+ pipeline.SendQueryPrepared(bi.sd.Name, c.eqb.ParamValues, c.eqb.ParamFormats, c.eqb.ResultFormats)
+ }
+ }
+
+ err := pipeline.Sync()
+ if err != nil {
+ return &pipelineBatchResults{ctx: ctx, conn: c, err: err, closed: true}
+ }
+
+ return &pipelineBatchResults{
+ ctx: ctx,
+ conn: c,
+ pipeline: pipeline,
+ b: b,
+ }
+}
+
+func (c *Conn) sanitizeForSimpleQuery(sql string, args ...any) (string, error) {
+ if c.pgConn.ParameterStatus("standard_conforming_strings") != "on" {
+ return "", errors.New("simple protocol queries must be run with standard_conforming_strings=on")
+ }
+
+ if c.pgConn.ParameterStatus("client_encoding") != "UTF8" {
+ return "", errors.New("simple protocol queries must be run with client_encoding=UTF8")
+ }
+
+ var err error
+ valueArgs := make([]any, len(args))
+ for i, a := range args {
+ valueArgs[i], err = convertSimpleArgument(c.typeMap, a)
+ if err != nil {
+ return "", err
+ }
+ }
+
+ return sanitize.SanitizeSQL(sql, valueArgs...)
+}
+
+// LoadType inspects the database for typeName and produces a pgtype.Type suitable for registration. typeName must be
+// the name of a type where the underlying type(s) is already understood by pgx. It is for derived types. In particular,
+// typeName must be one of the following:
+// - An array type name of a type that is already registered. e.g. "_foo" when "foo" is registered.
+// - A composite type name where all field types are already registered.
+// - A domain type name where the base type is already registered.
+// - An enum type name.
+// - A range type name where the element type is already registered.
+// - A multirange type name where the element type is already registered.
+func (c *Conn) LoadType(ctx context.Context, typeName string) (*pgtype.Type, error) {
+ var oid uint32
+
+ err := c.QueryRow(ctx, "select $1::text::regtype::oid;", typeName).Scan(&oid)
+ if err != nil {
+ return nil, err
+ }
+
+ var typtype string
+ var typbasetype uint32
+
+ err = c.QueryRow(ctx, "select typtype::text, typbasetype from pg_type where oid=$1", oid).Scan(&typtype, &typbasetype)
+ if err != nil {
+ return nil, err
+ }
+
+ switch typtype {
+ case "b": // array
+ elementOID, err := c.getArrayElementOID(ctx, oid)
+ if err != nil {
+ return nil, err
+ }
+
+ dt, ok := c.TypeMap().TypeForOID(elementOID)
+ if !ok {
+ return nil, errors.New("array element OID not registered")
+ }
+
+ return &pgtype.Type{Name: typeName, OID: oid, Codec: &pgtype.ArrayCodec{ElementType: dt}}, nil
+ case "c": // composite
+ fields, err := c.getCompositeFields(ctx, oid)
+ if err != nil {
+ return nil, err
+ }
+
+ return &pgtype.Type{Name: typeName, OID: oid, Codec: &pgtype.CompositeCodec{Fields: fields}}, nil
+ case "d": // domain
+ dt, ok := c.TypeMap().TypeForOID(typbasetype)
+ if !ok {
+ return nil, errors.New("domain base type OID not registered")
+ }
+
+ return &pgtype.Type{Name: typeName, OID: oid, Codec: dt.Codec}, nil
+ case "e": // enum
+ return &pgtype.Type{Name: typeName, OID: oid, Codec: &pgtype.EnumCodec{}}, nil
+ case "r": // range
+ elementOID, err := c.getRangeElementOID(ctx, oid)
+ if err != nil {
+ return nil, err
+ }
+
+ dt, ok := c.TypeMap().TypeForOID(elementOID)
+ if !ok {
+ return nil, errors.New("range element OID not registered")
+ }
+
+ return &pgtype.Type{Name: typeName, OID: oid, Codec: &pgtype.RangeCodec{ElementType: dt}}, nil
+ case "m": // multirange
+ elementOID, err := c.getMultiRangeElementOID(ctx, oid)
+ if err != nil {
+ return nil, err
+ }
+
+ dt, ok := c.TypeMap().TypeForOID(elementOID)
+ if !ok {
+ return nil, errors.New("multirange element OID not registered")
+ }
+
+ return &pgtype.Type{Name: typeName, OID: oid, Codec: &pgtype.MultirangeCodec{ElementType: dt}}, nil
+ default:
+ return &pgtype.Type{}, errors.New("unknown typtype")
+ }
+}
+
+func (c *Conn) getArrayElementOID(ctx context.Context, oid uint32) (uint32, error) {
+ var typelem uint32
+
+ err := c.QueryRow(ctx, "select typelem from pg_type where oid=$1", oid).Scan(&typelem)
+ if err != nil {
+ return 0, err
+ }
+
+ return typelem, nil
+}
+
+func (c *Conn) getRangeElementOID(ctx context.Context, oid uint32) (uint32, error) {
+ var typelem uint32
+
+ err := c.QueryRow(ctx, "select rngsubtype from pg_range where rngtypid=$1", oid).Scan(&typelem)
+ if err != nil {
+ return 0, err
+ }
+
+ return typelem, nil
+}
+
+func (c *Conn) getMultiRangeElementOID(ctx context.Context, oid uint32) (uint32, error) {
+ var typelem uint32
+
+ err := c.QueryRow(ctx, "select rngtypid from pg_range where rngmultitypid=$1", oid).Scan(&typelem)
+ if err != nil {
+ return 0, err
+ }
+
+ return typelem, nil
+}
+
+func (c *Conn) getCompositeFields(ctx context.Context, oid uint32) ([]pgtype.CompositeCodecField, error) {
+ var typrelid uint32
+
+ err := c.QueryRow(ctx, "select typrelid from pg_type where oid=$1", oid).Scan(&typrelid)
+ if err != nil {
+ return nil, err
+ }
+
+ var fields []pgtype.CompositeCodecField
+ var fieldName string
+ var fieldOID uint32
+ rows, _ := c.Query(ctx, `select attname, atttypid
+from pg_attribute
+where attrelid=$1
+ and not attisdropped
+ and attnum > 0
+order by attnum`,
+ typrelid,
+ )
+ _, err = ForEachRow(rows, []any{&fieldName, &fieldOID}, func() error {
+ dt, ok := c.TypeMap().TypeForOID(fieldOID)
+ if !ok {
+ return fmt.Errorf("unknown composite type field OID: %v", fieldOID)
+ }
+ fields = append(fields, pgtype.CompositeCodecField{Name: fieldName, Type: dt})
+ return nil
+ })
+ if err != nil {
+ return nil, err
+ }
+
+ return fields, nil
+}
+
+func (c *Conn) deallocateInvalidatedCachedStatements(ctx context.Context) error {
+ if txStatus := c.pgConn.TxStatus(); txStatus != 'I' && txStatus != 'T' {
+ return nil
+ }
+
+ if c.descriptionCache != nil {
+ c.descriptionCache.RemoveInvalidated()
+ }
+
+ var invalidatedStatements []*pgconn.StatementDescription
+ if c.statementCache != nil {
+ invalidatedStatements = c.statementCache.GetInvalidated()
+ }
+
+ if len(invalidatedStatements) == 0 {
+ return nil
+ }
+
+ pipeline := c.pgConn.StartPipeline(ctx)
+ defer pipeline.Close()
+
+ for _, sd := range invalidatedStatements {
+ pipeline.SendDeallocate(sd.Name)
+ }
+
+ err := pipeline.Sync()
+ if err != nil {
+ return fmt.Errorf("failed to deallocate cached statement(s): %w", err)
+ }
+
+ err = pipeline.Close()
+ if err != nil {
+ return fmt.Errorf("failed to deallocate cached statement(s): %w", err)
+ }
+
+ c.statementCache.RemoveInvalidated()
+ for _, sd := range invalidatedStatements {
+ delete(c.preparedStatements, sd.Name)
+ }
+
+ return nil
+}