diff options
Diffstat (limited to 'src/interfaces/perl5/Pg.pm')
| -rw-r--r-- | src/interfaces/perl5/Pg.pm | 290 |
1 files changed, 201 insertions, 89 deletions
diff --git a/src/interfaces/perl5/Pg.pm b/src/interfaces/perl5/Pg.pm index 8f0ba77edc7..2d6f7a15b7c 100644 --- a/src/interfaces/perl5/Pg.pm +++ b/src/interfaces/perl5/Pg.pm @@ -1,6 +1,6 @@ #------------------------------------------------------- # -# $Id: Pg.pm,v 1.7 1998/06/01 16:41:19 mergl Exp $ +# $Id: Pg.pm,v 1.8 1998/09/27 19:12:22 mergl Exp $ # # Copyright (c) 1997, 1998 Edmund Mergl # @@ -22,32 +22,46 @@ require 5.002; # Items to export into callers namespace by default. @EXPORT = qw( PQconnectdb - PQconndefaults + PQsetdbLogin PQsetdb + PQconndefaults PQfinish PQreset + PQrequestCancel PQdb PQuser + PQpass PQhost - PQoptions PQport PQtty + PQoptions PQstatus PQerrorMessage + PQsocket + PQbackendPID PQtrace PQuntrace PQexec + PQnotifies + PQsendQuery + PQgetResult + PQisBusy + PQconsumeInput PQgetline - PQendcopy PQputline - PQnotifies + PQgetlineAsync + PQputnbytes + PQendcopy + PQmakeEmptyPGresult PQresultStatus PQntuples PQnfields + PQbinaryTuples PQfname PQfnumber PQftype PQfsize + PQfmod PQcmdStatus PQoidStatus PQcmdTuples @@ -55,8 +69,9 @@ require 5.002; PQgetlength PQgetisnull PQclear - PQprintTuples PQprint + PQdisplayTuples + PQprintTuples PQlo_open PQlo_close PQlo_read @@ -84,7 +99,7 @@ require 5.002; PGRES_InvalidOid ); -$Pg::VERSION = '1.7.4'; +$Pg::VERSION = '1.8.0'; sub AUTOLOAD { # This AUTOLOAD is used to 'autoload' constants from the constant() @@ -145,15 +160,15 @@ Pg - Perl5 extension for PostgreSQL new style: use Pg; - $conn = Pg::connectdb("dbname = template1"); - $result = $conn->exec("create database test"); + $conn = Pg::connectdb("dbname=template1"); + $result = $conn->exec("create database pgtest"); -you may also use the old style: +old style (depreciated): use Pg; $conn = PQsetdb('', '', '', '', template1); - $result = PQexec($conn, "create database test"); + $result = PQexec($conn, "create database pgtest"); PQclear($result); PQfinish($conn); @@ -232,41 +247,58 @@ implemented in perl using lists or hash. =head1 FUNCTIONS The functions have been divided into three sections: -Connection, Result, Large Objects. +Connection, Result, Large Objects. For details please +read L<libpq>. =head2 1. Connection With these functions you can establish and close a connection to a database. In Libpq a connection is represented by a structure called -PGconn. Using the appropriate methods you can access almost all -fields of this structure. +PGconn. + +When opening a connection a given database name is always converted to +lower-case, unless it is surrounded by double quotes. All unspecified +parameters are replaced by environment variables or by hard coded defaults: + + parameter environment variable hard coded default + -------------------------------------------------- + host PGHOST localhost + port PGPORT 5432 + options PGOPTIONS "" + tty PGTTY "" + dbname PGDATABASE current userid + user PGUSER current userid + password PGPASSWORD "" + +Using appropriate methods you can access almost all fields of the +returned PGconn structure. + + $conn = Pg::setdbLogin($pghost, $pgport, $pgoptions, $pgtty, $dbname, $login, $pwd) + +Opens a new connection to the backend. The connection identifier $conn +( a pointer to the PGconn structure ) must be used in subsequent commands +for unique identification. Before using $conn you should call $conn->status +to ensure, that the connection was properly made. $conn = Pg::setdb($pghost, $pgport, $pgoptions, $pgtty, $dbname) -Opens a new connection to the backend. You may use an empty string for -any argument, in which case first the environment is checked and then -hard-coded defaults are used. The connection identifier $conn ( a pointer -to the PGconn structure ) must be used in subsequent commands for unique -identification. Before using $conn you should call $conn->status to ensure, -that the connection was properly made. Use the methods below to access -the contents of the PGconn structure. +The method setdb should be used when username/password authentication is +not needed. $conn = Pg::connectdb("option1=value option2=value ...") -Opens a new connection to the backend using connection information in a string. -Possible options are: dbname, host, user, password, authtype, port, tty, options. -The database-name will be converted to lower-case, unless it is surrounded by -double quotes. The connection identifier $conn (a pointer to the PGconn structure) -must be used in subsequent commands for unique identification. Before using $conn -you should call $conn->status to ensure, that the connection was properly made. -Use the methods below to access the contents of the PGconn structure. +Opens a new connection to the backend using connection information in a +string. Possible options are: host, port, options, tty, dbname, user, password. +The connection identifier $conn (a pointer to the PGconn structure) +must be used in subsequent commands for unique identification. Before using +$conn you should call $conn->status to ensure, that the connection was +properly made. $Option_ref = Pg::conndefaults() while(($key, $val) = each %$Option_ref) { print "$key, $val\n"; - } Returns a reference to a hash containing as keys all possible options for connectdb(). The values are the current defaults. This function differs from @@ -275,13 +307,20 @@ his C-counterpart, which returns the complete conninfoOption structure. PQfinish($conn) Old style only ! -Closes the connection to the backend and frees all memory. +Closes the connection to the backend and frees the connection data structure. $conn->reset Resets the communication port with the backend and tries to establish a new connection. + $ret = $conn->requestCancel + +Abandon processing of the current query. Regardless of the return value of +requestCancel, the application must continue with the normal result-reading +sequence using getResult. If the current query is part of a transaction, +cancellation will abort the whole transaction. + $dbname = $conn->db Returns the database name of the connection. @@ -290,13 +329,13 @@ Returns the database name of the connection. Returns the Postgres user name of the connection. - $pghost = $conn->host + $pguser = $conn->pass -Returns the host name of the connection. +Returns the Postgres password of the connection. - $pgoptions = $conn->options + $pghost = $conn->host -Returns the options used in the connection. +Returns the host name of the connection. $pgport = $conn->port @@ -306,6 +345,10 @@ Returns the port of the connection. Returns the tty of the connection. + $pgoptions = $conn->options + +Returns the options used in the connection. + $status = $conn->status Returns the status of the connection. For comparing the status @@ -318,6 +361,15 @@ you may use the following constants: Returns the last error message associated with this connection. + $fd = $conn->socket + +Obtain the file descriptor number for the backend connection socket. +A result of -1 indicates that no backend connection is currently open. + + $pid = $conn->backendPID + +Returns the process-id of the corresponding backend proceess. + $conn->trace(debug_port) Messages passed between frontend and backend are echoed to the @@ -338,6 +390,39 @@ structure has to be freed using PQfree. Before using $result you should call resultStatus to ensure, that the query was properly executed. + ($table, $pid) = $conn->notifies + +Checks for asynchronous notifications. This functions differs from +the C-counterpart which returns a pointer to a new allocated structure, +whereas the perl implementation returns a list. $table is the table +which has been listened to and $pid is the process id of the backend. + + + $ret = $conn->sendQuery($string, $query) + +Submit a query to Postgres without waiting for the result(s). After +successfully calling PQsendQuery, call PQgetResult one or more times +to obtain the query results. PQsendQuery may not be called again until +getResult has returned NULL, indicating that the query is done. + + $result = $conn->getResult + +Wait for the next result from a prior PQsendQuery, and return it. NULL +is returned when the query is complete and there will be no more results. +getResult will block only if a query is active and the necessary response +data has not yet been read by PQconsumeInput. + + $ret = $conn->isBusy + +Returns TRUE if a query is busy, that is, PQgetResult would block waiting +for input. A FALSE return indicates that PQgetResult can be called with +assurance of not blocking. + + $result = $conn->consumeInput + +If input is available from the backend, consume it. After calling consumeInput, +the application may check isBusy and/or notifies to see if their state has changed. + $ret = $conn->getline($string, $length) Reads a string up to $length - 1 characters from the backend. @@ -346,26 +431,34 @@ and 1 if the buffer is full. If a line consists of the two characters "\." the backend has finished sending the results of the copy command. - $conn->putline($string) + $ret = $conn->putline($string) Sends a string to the backend. The application must explicitly send the two characters "\." to indicate to the backend that it has finished sending its data. + $ret = $conn->getlineAsync($buffer, $bufsize) + +Non-blocking version of getline. It reads up to $bufsize +characters from the backend. getlineAsync returns -1 if +the end-of-copy-marker has been recognized, 0 if no data +is avilable, and >0 the number of bytes returned. + + $ret = $conn->putnbytes($buffer, $nbytes) + +Sends n bytes to the backend. Returns 0 if OK, EOF if not. + $ret = $conn->endcopy This function waits until the backend has finished the copy. It should either be issued when the last string has been sent to the backend using putline or when the last string has been received from the backend using getline. endcopy returns -0 on success, nonzero otherwise. +0 on success, 1 on failure. - ($table, $pid) = $conn->notifies + $result = $conn->makeEmptyPGresult($status); -Checks for asynchronous notifications. This functions differs from -the C-counterpart which returns a pointer to a new allocated structure, -whereas the perl implementation returns a list. $table is the table -which has been listened to and $pid is the process id of the backend. +Returns a newly allocated, initialized result with given status. =head2 2. Result @@ -375,6 +468,21 @@ investigate the results. In Libpq the result of a command is represented by a structure called PGresult. Using the appropriate methods you can access almost all fields of this structure. + $result_status = $result->resultStatus + +Returns the status of the result. For comparing the status you +may use one of the following constants depending upon the +command executed: + + - PGRES_EMPTY_QUERY + - PGRES_COMMAND_OK + - PGRES_TUPLES_OK + - PGRES_COPY_OUT + - PGRES_COPY_IN + - PGRES_BAD_RESPONSE + - PGRES_NONFATAL_ERROR + - PGRES_FATAL_ERROR + Use the functions below to access the contents of the PGresult structure. $ntuples = $result->ntuples @@ -385,6 +493,10 @@ Returns the number of tuples in the query result. Returns the number of fields in the query result. + $ret = $result->binaryTuples + +Returns 1 if the tuples in the query result are bianry. + $fname = $result->fname($field_num) Returns the field name associated with the given field number. @@ -402,34 +514,10 @@ Returns the oid of the type of the given field number. Returns the size in bytes of the type of the given field number. It returns -1 if the field has a variable length. - $value = $result->getvalue($tup_num, $field_num) - -Returns the value of the given tuple and field. This is -a null-terminated ASCII string. Binary cursors will not -work. - - $length = $result->getlength($tup_num, $field_num) - -Returns the length of the value for a given tuple and field. - - $null_status = $result->getisnull($tup_num, $field_num) - -Returns the NULL status for a given tuple and field. + $fmod = $result->fmod($field_num) - $result_status = $result->resultStatus - -Returns the status of the result. For comparing the status you -may use one of the following constants depending upon the -command executed: - - - PGRES_EMPTY_QUERY - - PGRES_COMMAND_OK - - PGRES_TUPLES_OK - - PGRES_COPY_OUT - - PGRES_COPY_IN - - PGRES_BAD_RESPONSE - - PGRES_NONFATAL_ERROR - - PGRES_FATAL_ERROR +Returns the type-specific modification data of the field associated +with the given field index. Field indices start at 0. $cmdStatus = $result->cmdStatus @@ -449,9 +537,30 @@ inserted tuple. In case the last query was an INSERT or DELETE command it returns the number of affected tuples. - $result->printTuples($fout, $printAttName, $terseOutput, $width) + $value = $result->getvalue($tup_num, $field_num) -Kept for backward compatibility. Use print. +Returns the value of the given tuple and field. This is +a null-terminated ASCII string. Binary cursors will not +work. + + $length = $result->getlength($tup_num, $field_num) + +Returns the length of the value for a given tuple and field. + + $null_status = $result->getisnull($tup_num, $field_num) + +Returns the NULL status for a given tuple and field. + + PQclear($result) + +Old style only ! +Frees all memory of the given result. + + $res->fetchrow + +New style only ! +Fetches the next row from the server and returns NULL if all rows +have been processed. Columns which have NULL as value will be set to C<undef>. $result->print($fout, $header, $align, $standard, $html3, $expanded, $pager, $fieldSep, $tableOpt, $caption, ...) @@ -464,10 +573,13 @@ are boolean flags. The arguments $fieldSep, $tableOpt, $caption are strings. You may append additional strings, which will be taken as replacement for the field names. - PQclear($result) + $result->displayTuples($fp, $fillAlign, $fieldSep, $printHeader, qiet) -Old style only ! -Frees all memory of the given result. +Kept for backward compatibility. Use print. + + $result->printTuples($fout, $printAttName, $terseOutput, $width) + +Kept for backward compatibility. Use print. =head2 3. Large Objects @@ -478,22 +590,6 @@ system interface with analogies of open, close, read, write, lseek, tell. In order to get a consistent naming, all function names have been prepended with 'PQ' (old style only). - $lobjId = $conn->lo_creat($mode) - -Creates a new large object. $mode is a bit-mask describing -different attributes of the new object. Use the following constants: - - - PGRES_INV_SMGRMASK - - PGRES_INV_ARCHIVE - - PGRES_INV_WRITE - - PGRES_INV_READ - -Upon failure it returns PGRES_InvalidOid. - - $ret = $conn->lo_unlink($lobjId) - -Deletes a large object. Returns -1 upon failure. - $lobj_fd = $conn->lo_open($lobjId, $mode) Opens an existing large object and returns an object id. @@ -519,11 +615,27 @@ Returns the number of bytes written and -1 upon failure. Change the current read or write location on the large object $obj_id. Currently $whence can only be 0 (L_SET). + $lobjId = $conn->lo_creat($mode) + +Creates a new large object. $mode is a bit-mask describing +different attributes of the new object. Use the following constants: + + - PGRES_INV_SMGRMASK + - PGRES_INV_ARCHIVE + - PGRES_INV_WRITE + - PGRES_INV_READ + +Upon failure it returns PGRES_InvalidOid. + $location = $conn->lo_tell($lobj_fd) Returns the current read or write location on the large object $lobj_fd. + $ret = $conn->lo_unlink($lobjId) + +Deletes a large object. Returns -1 upon failure. + $lobjId = $conn->lo_import($filename) Imports a Unix file as large object and returns |