Package org.postgresql

Interface PGConnection

All Known Subinterfaces:
BaseConnection
All Known Implementing Classes:
PgConnection
public interface PGConnection
This interface defines the public PostgreSQL extensions to java.sql.Connection. All Connections returned by the PostgreSQL driver implement PGConnection.

  • Method Details

    • createArrayOf

      Array createArrayOf(String typeName, @Nullable Object elements) throws SQLException
      Creates an Array wrapping elements. This is similar to Connection.createArrayOf(String, Object[]), but also provides support for primitive arrays.
      Parameters:
      typeName - The SQL name of the type to map the elements to. Must not be null.
      elements - The array of objects to map. A null value will result in an Array representing null.
      Returns:
      An Array wrapping elements.
      Throws:
      SQLException - If for some reason the array cannot be created.
      See Also:

    • getNotifications

      PGNotification[] getNotifications() throws SQLException
      This method returns any notifications that have been received since the last call to this method. Returns null if there have been no notifications.
      Returns:
      notifications that have been received
      Throws:
      SQLException - if something wrong happens
      Since:
      7.3

    • getNotifications

      PGNotification[] getNotifications(int timeoutMillis) throws SQLException
      This method returns any notifications that have been received since the last call to this method. Returns null if there have been no notifications. A timeout can be specified so the driver waits for notifications.
      Parameters:
      timeoutMillis - when 0, blocks forever. when > 0, blocks up to the specified number of millis or until at least one notification has been received. If more than one notification is about to be received, these will be returned in one batch.
      Returns:
      notifications that have been received
      Throws:
      SQLException - if something wrong happens
      Since:
      43

    • getCopyAPI

      CopyManager getCopyAPI() throws SQLException
      This returns the COPY API for the current connection.
      Returns:
      COPY API for the current connection
      Throws:
      SQLException - if something wrong happens
      Since:
      8.4

    • getLargeObjectAPI

      LargeObjectManager getLargeObjectAPI() throws SQLException
      This returns the LargeObject API for the current connection.
      Returns:
      LargeObject API for the current connection
      Throws:
      SQLException - if something wrong happens
      Since:
      7.3

    • getFastpathAPI

      @Deprecated Fastpath getFastpathAPI() throws SQLException
      Deprecated.
      This API is somewhat obsolete, as one may achieve similar performance and greater functionality by setting up a prepared statement to define the function call. Then, executing the statement with binary transmission of parameters and results substitutes for a fast-path function call.
      This returns the Fastpath API for the current connection.
      Returns:
      Fastpath API for the current connection
      Throws:
      SQLException - if something wrong happens
      Since:
      7.3

    • addDataType

      @Deprecated void addDataType(String type, String className)
      Deprecated.
      As of 8.0, replaced by addDataType(String, Class). This deprecated method does not work correctly for registering classes that cannot be directly loaded by the JDBC driver's classloader.
      This allows client code to add a handler for one of org.postgresql's more unique data types. It is approximately equivalent to addDataType(type, Class.forName(name)).
      Parameters:
      type - JDBC type name
      className - class name
      Throws:
      RuntimeException - if the type cannot be registered (class not found, etc).

    • addDataType

      void addDataType(String type, Class<? extends PGobject> klass) throws SQLException

      This allows client code to add a handler for one of org.postgresql's more unique data types.

      NOTE: This is not part of JDBC, but an extension.

      The best way to use this is as follows:

       ...
 ((org.postgresql.PGConnection)myconn).addDataType("mytype", my.class.name.class);
 ...

      where myconn is an open Connection to org.postgresql.

      The handling class must extend org.postgresql.util.PGobject

      Parameters:
      type - the PostgreSQL type to register
      klass - the class implementing the Java representation of the type; this class must implement PGobject).
      Throws:
      SQLException - if klass does not implement PGobject).
      Since:
      8.0
      See Also:

    • setPrepareThreshold

      void setPrepareThreshold(int threshold)
      Set the default statement reuse threshold before enabling server-side prepare. See PGStatement.setPrepareThreshold(int) for details.
      Parameters:
      threshold - the new threshold
      Since:
      build 302

    • getPrepareThreshold

      int getPrepareThreshold()
      Get the default server-side prepare reuse threshold for statements created from this connection.
      Returns:
      the current threshold
      Since:
      build 302

    • setDefaultFetchSize

      void setDefaultFetchSize(int fetchSize) throws SQLException
      Set the default fetch size for statements created from this connection.
      Parameters:
      fetchSize - new default fetch size
      Throws:
      SQLException - if specified negative fetchSize parameter
      See Also:

    • getDefaultFetchSize

      int getDefaultFetchSize()
      Get the default fetch size for statements created from this connection.
      Returns:
      current state for default fetch size
      See Also:

    • getBackendPID

      int getBackendPID()
      Return the process ID (PID) of the backend server process handling this connection.
      Returns:
      PID of backend server process.

    • cancelQuery

      void cancelQuery() throws SQLException
      Sends a query cancellation for this connection.
      Throws:
      SQLException - if there are problems cancelling the query

    • escapeIdentifier

      String escapeIdentifier(String identifier) throws SQLException
      Return the given string suitably quoted to be used as an identifier in an SQL statement string. Quotes are added only if necessary (i.e., if the string contains non-identifier characters or would be case-folded). Embedded quotes are properly doubled.
      Parameters:
      identifier - input identifier
      Returns:
      the escaped identifier
      Throws:
      SQLException - if something goes wrong

    • escapeLiteral

      String escapeLiteral(String literal) throws SQLException
      Return the given string suitably quoted to be used as a string literal in an SQL statement string. Embedded single-quotes and backslashes are properly doubled. Note that quote_literal returns null on null input.
      Parameters:
      literal - input literal
      Returns:
      the quoted literal
      Throws:
      SQLException - if something goes wrong

    • getPreferQueryMode

      PreferQueryMode getPreferQueryMode()

      Returns the query mode for this connection.

      When running in simple query mode, certain features are not available: callable statements, partial result set fetch, bytea type, etc.

      The list of supported features is subject to change.

      Returns:
      the preferred query mode
      See Also:

    • getAutosave

      AutoSave getAutosave()
      Connection configuration regarding automatic per-query savepoints.
      Returns:
      connection configuration regarding automatic per-query savepoints
      See Also:

    • setAutosave

      void setAutosave(AutoSave autoSave)
      Configures if connection should use automatic savepoints.
      Parameters:
      autoSave - connection configuration regarding automatic per-query savepoints
      See Also:

    • getReplicationAPI

      PGReplicationConnection getReplicationAPI()
      Returns:
      replication API for the current connection

    • alterUserPassword

      default void alterUserPassword(String user, char[] newPassword, @Nullable String encryptionType) throws SQLException
      Change a user's password to the specified new password.

      If the specific encryption type is not specified, this method defaults to querying the database server for the server's default password_encryption. This method does not send the new password in plain text to the server. Instead, it encrypts the password locally and sends the encoded hash so that the plain text password is never sent on the wire.

      Acceptable values for encryptionType are null, "md5", or "scram-sha-256". Users should avoid "md5" unless they are explicitly targeting an older server that does not support the more secure SCRAM.

      Parameters:
      user - The username of the database user
      newPassword - The new password for the database user. The implementation will zero out the array after use
      encryptionType - The type of password encryption to use or null if the database server default should be used.
      Throws:
      SQLException - If the password could not be altered

    • getParameterStatuses

      Map<String,String> getParameterStatuses()

      Returns the current values of all parameters reported by the server.

      PostgreSQL reports values for a subset of parameters (GUCs) to the client at connect-time, then sends update messages whenever the values change during a session. PgJDBC records the latest values and exposes it to client applications via getParameterStatuses().

      PgJDBC exposes individual accessors for some of these parameters as listed below. They are more backwards-compatible and should be preferred where possible.

      Not all parameters are reported, only those marked GUC_REPORT in the source code. The pg_settings view does not expose information about which parameters are reportable. PgJDBC's map will only contain the parameters the server reports values for, so you cannot use this method as a substitute for running a SHOW paramname; or SELECT current_setting('paramname'); query for arbitrary parameters.

      Parameter names are case-insensitive and case-preserving in this map, like in PostgreSQL itself. So DateStyle and datestyle are the same key.

      As of PostgreSQL 11 the reportable parameter list, and related PgJDBC interfaces or assessors, are:

      Note that some PgJDBC operations will change server parameters automatically.

      Returns:
      unmodifiable map of case-insensitive parameter names to parameter values
      Since:
      42.2.6

    • getParameterStatus

      @Nullable String getParameterStatus(String parameterName)
      Shorthand for getParameterStatuses().get(...) .
      Parameters:
      parameterName - case-insensitive parameter name
      Returns:
      parameter value if defined, or null if no parameter known
      Since:
      42.2.6
      See Also:

    • setAdaptiveFetch

      void setAdaptiveFetch(boolean adaptiveFetch)
      Turn on/off adaptive fetch for connection. Existing statements and resultSets won't be affected by change here.
      Parameters:
      adaptiveFetch - desired state of adaptive fetch.

    • getAdaptiveFetch

      boolean getAdaptiveFetch()
      Get state of adaptive fetch for connection.
      Returns:
      state of adaptive fetch (turned on or off)