Константи, описані нижче — визначені цим розширенням, тож доступні, коли розширення скомпільовано як частина PHP або динамічно підключене під час виконання.
PGSQL_LIBPQ_VERSION
    (string)
   PGSQL_LIBPQ_VERSION_STR
    (string)
   PGSQL_LIBPQ_VERSION,
     and using PGSQL_LIBPQ_VERSION_STR is deprecated.
    
   PGSQL_ASSOC
    (int)
   PGSQL_NUM
    (int)
   PGSQL_BOTH
    (int)
   PGSQL_CONNECT_FORCE_NEW
    (int)
   PGSQL_CONNECT_ASYNC
    (int)
   PGSQL_CONNECTION_AUTH_OK
    (int)
   PGSQL_CONNECTION_AWAITING_RESPONSE
    (int)
   PGSQL_CONNECTION_BAD
    (int)
   PGSQL_CONNECTION_MADE
    (int)
   PGSQL_CONNECTION_OK
    (int)
   PGSQL_CONNECTION_SETENV
    (int)
   PGSQL_CONNECTION_SSL_STARTUP
    (int)
   PGSQL_CONNECTION_STARTED
    (int)
   PGSQL_SEEK_SET
    (int)
   PGSQL_SEEK_CUR
    (int)
   PGSQL_SEEK_END
    (int)
   PGSQL_EMPTY_QUERY
    (int)
   PGSQL_COMMAND_OK
    (int)
   PGSQL_TUPLES_OK
    (int)
   SELECT or SHOW).
    
   PGSQL_TUPLES_CHUNK
    (int)
   SELECT commands when
     pg_set_chunked_rows_size() is set.
     The result set is divided into multiple chunks, each containing a predefined number of rows.
     Available as of PHP 8.4.0 and libpq 17.
    
   PGSQL_COPY_OUT
    (int)
   PGSQL_COPY_IN
    (int)
   PGSQL_BAD_RESPONSE
    (int)
   PGSQL_NONFATAL_ERROR
    (int)
   PGSQL_FATAL_ERROR
    (int)
   PGSQL_TRANSACTION_IDLE
    (int)
   PGSQL_TRANSACTION_ACTIVE
    (int)
   PGSQL_TRANSACTION_INTRANS
    (int)
   PGSQL_TRANSACTION_INERROR
    (int)
   PGSQL_TRANSACTION_UNKNOWN
    (int)
   PGSQL_DIAG_SEVERITY
    (int)
   ERROR,
     FATAL, or PANIC (in an error message), or
     WARNING, NOTICE, DEBUG,
     INFO, or LOG (in a notice message), or a localized
     translation of one of these. Always present.
    
   PGSQL_DIAG_SQLSTATE
    (int)
   PGSQL_DIAG_MESSAGE_PRIMARY
    (int)
   PGSQL_DIAG_MESSAGE_DETAIL
    (int)
   PGSQL_DIAG_MESSAGE_HINT
    (int)
   PGSQL_DIAG_STATEMENT_POSITION
    (int)
   PGSQL_DIAG_INTERNAL_POSITION
    (int)
   PG_DIAG_STATEMENT_POSITION field, but
     it is used when the cursor position refers to an internally generated
     command rather than the one submitted by the client. The
     PG_DIAG_INTERNAL_QUERY field will always appear when this
     field appears.
    
   PGSQL_DIAG_INTERNAL_QUERY
    (int)
   PGSQL_DIAG_CONTEXT
    (int)
   PGSQL_DIAG_SOURCE_FILE
    (int)
   PGSQL_DIAG_SOURCE_LINE
    (int)
   PGSQL_DIAG_SOURCE_FUNCTION
    (int)
   PGSQL_DIAG_SCHEMA_NAME
    (int)
   PGSQL_DIAG_TABLE_NAME
    (int)
   PGSQL_DIAG_COLUMN_NAME
    (int)
   PGSQL_DIAG_DATATYPE_NAME
    (int)
   PGSQL_DIAG_CONSTRAINT_NAME
    (int)
   PGSQL_ERRORS_TERSE
    (int)
   PGSQL_ERRORS_DEFAULT
    (int)
   PGSQL_ERRORS_VERBOSE
    (int)
   PGSQL_ERRORS_SQLSTATE
    (int)
   SQLSTATE error code.
     If no error code is available, the output is like
     PGSQL_ERRORS_TERSE mode.
     Before PostgreSQL 11.1, the output is always the same
     as in PGSQL_ERRORS_TERSE mode.
    
   PGSQL_NOTICE_LAST
    (int)
   PGSQL_NOTICE_ALL
    (int)
   PGSQL_NOTICE_CLEAR
    (int)
   PGSQL_STATUS_LONG
    (int)
   PGSQL_STATUS_STRING
    (int)
   PGSQL_CONV_IGNORE_DEFAULT
    (int)
   PGSQL_CONV_FORCE_NULL
    (int)
   NULL in place of an empty string.
    
   PGSQL_CONV_IGNORE_NOT_NULL
    (int)
   null into SQL NOT NULL columns.
    
   PGSQL_DML_NO_CONV
    (int)
   PGSQL_DML_EXEC
    (int)
   PGSQL_DML_ASYNC
    (int)
   PGSQL_DML_STRING
    (int)
   PGSQL_DML_ESCAPE
    (int)
   PGSQL_POLLING_FAILED
    (int)
   PGSQL_POLLING_READING
    (int)
   PGSQL_POLLING_WRITING
    (int)
   PGSQL_POLLING_OK
    (int)
   PGSQL_POLLING_ACTIVE
    (int)
   PGSQL_DIAG_SEVERITY_NONLOCALIZED
    (int)
   PGSQL_SHOW_CONTEXT_NEVER
    (int)
   PGSQL_SHOW_CONTEXT_ERRORS
    (int)
   PGSQL_SHOW_CONTEXT_ALWAYS
    (int)
   PGSQL_TRACE_SUPPRESS_TIMESTAMPS
    (int)
   PGSQL_TRACE_REGRESS_MODE
    (int)
   