Pgtcl Reference Manual

Table of Contents

Preface

1. Overview

2. Building and Installing pgtcl-ng

2.1. Building and Installing on Unix-like Systems

2.1.1. Prerequisites for Unix-like Systems

2.1.2. Building and Installing - Unix-like Systems

2.2. Building and Installing on Windows (MinGW tools)

2.2.1. Prerequisites for Windows Systems (MinGW tools)

2.2.2. Building and Installing - Windows Systems (MinGW tools)

2.3. Building and Installing on Windows Systems (Borland Compiler)

2.3.1. Prerequisites for Windows Systems (Borland Compiler)

2.3.2. Building and Installing - Windows Systems (Borland Compiler)

2.4. Building and Installing on MacOS 10

2.4.1. Prerequisites for MacOS Systems

2.4.2. Building on MacOS

3. Loading pgtcl into an Application

3.1. Using the Tcl Package Command

3.1.1. "Package require" setup for Unix-like systems

3.1.2. "Package require" setup for Windows

3.2. Directly loading libpgtcl

3.3. Linking libpgtcl Into an Application

4. pgtcl Command Reference

4.1. Database Connection Control Commands

pg_connect — Open a connection to the server

pg_disconnect — Close a connection to the server

pg_conndefaults — Get connection options and their defaults

4.2. Connection Status Commands

pg_transaction_status — Get the current in-transaction status

pg_parameter_status — Get the value of a parameter from the database server

pg_backend_pid — Get the process ID (PID) of the backend

pg_server_version — Get the PostgreSQL server software version

4.3. Query Execution Commands

pg_exec — Execute an SQL command on the server

pg_execute — Execute an SQL command on the server and optionally loop over the results

pg_select — Execute an SQL command on the server and loop over the results

pg_exec_params — Execute a parameterized SQL command on the server

pg_exec_prepared — Execute a pre-prepared SQL command on the server

pg_describe_cursor — Get information about a cursor (portal)

pg_describe_prepared — Get information about a prepared statement

pg_result — Get information about a command result

pg_encrypt_password — Encrypt a password/username combination

pg_escape_string — Escape a string for use in an SQL string constant

pg_quote — Escape and quote a string for use as an SQL string literal

pg_escape_identifier — Escape a string for use as an SQL identifier (object name)

pg_escape_literal — Escape and quote a string for use as an SQL string literal

pg_escape_bytea — Escape a binary string for use in an SQL string constant with bytea (byte array) columns

pg_unescape_bytea — Unescape a string returned by an SQL query on a bytea (byte array) column, recovering the original binary string.

4.4. Asynchronous Query Processing Commands

pg_sendquery — Send an SQL command to the server for asynchronous execution

pg_sendquery_params — Send a parameterized SQL command to the server for asynchronous execution

pg_sendquery_prepared — Send a pre-prepared SQL command to the server for asynchronous execution

pg_isbusy — See if pg_getresult will block

pg_getresult — Wait for and return result from asynchronous SQL command

pg_cancelrequest — Cancel an in-progress asynchronous query

pg_blocking — Get or set the connection mode - blocking or nonblocking

pg_result_callback — Set a callback for asynchronous SQL command result availability

4.5. Notification and Notice Processing Commands

pg_listen — Set a callback for asynchronous notification messages

pg_on_connection_loss — Set a callback for unexpected connection loss

pg_notice_handler — Set a callback for notice or warning messages from the server

4.6. Large Object Processing Commands

pg_lo_creat — Create a large object

pg_lo_open — Open a large object

pg_lo_close — Close a large object

pg_lo_read — Read from a large object

pg_lo_write — Write to a large object

pg_lo_lseek — Seek to a position of a large object

pg_lo_lseek64 — Seek to a position of a large object, using a 64-bit offset

pg_lo_tell — Return the current seek position of a large object

pg_lo_tell64 — Return the current seek position of a large object, using 64-bit offsets

pg_lo_truncate — Truncate a large object, changing its size

pg_lo_truncate64 — Truncate a large object, changing its size, using a 64-bit offset

pg_lo_unlink — Delete a large object

pg_lo_import — Import a large object from a file

pg_lo_export — Export a large object to a file

5. Example Programs

5.1. Example - Connect and query with pg_exec

5.2. Example - Connect and query with pg_execute

5.3. Example - Get List of Databases

5.4. Example - The Different Ways to Get Query Results

5.5. Example - Large Objects - Picture Viewer, Part 1 - Store Pictures

5.6. Example - Large Objects - Picture Viewer, Part 2 - View Pictures

5.7. Example - Prepared Queries - Picture Viewer, Part 1 - Store Pictures

5.8. Example - Prepared Queries - Picture Viewer, Part 2 - View Pictures

5.9. Example - Bytea Escaping - Picture Viewer, Part 1 - Store Pictures

5.10. Example - Bytea Escaping - Picture Viewer, Part 2 - View Pictures

5.11. Example - Asynchronous Queries

5.12. Example - Asynchronous Query with Event-Driven Results

5.13. Example - COPY FROM and COPY TO