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PQparamCreate(3)               libpqtypes Manual              PQparamCreate(3)



NAME
       PQparamCreate,  PQparamCount  PQparamReset, PQparamClear - PGparam man-
       agement functions.

SYNOPSIS
       #include <libpqtypes.h>

       PGparam *PQparamCreate(const PGconn *conn);
       PGparam *PQparamDup(PGparam *param);
       int PQparamCount(PGparam *param);
       void PQparamReset(PGparam *param);
       void PQparamClear(PGparam *param);

DESCRIPTION
       These functions manage the opaque PGparam object.

       PQparamCreate() will allocate and  initialize  a  new  PGparam  object.
       After  the  create call, the PGparam object is ready for use.  WARNING:
       Only types that have been registered via PQregisterXXX, will be  avail-
       able to the param.  Meaning, the param is not updated with types regis-
       tered after the param is created.

       PQparamDup() will duplicate a given  PGparam,  including  any  internal
       values  that  have  already been put. This is useful in cases where you
       want to queue qeuries to execute at a later  time,  like  a  connection
       pooler.   The  problem  is  PGparamCreate requires a connection object,
       which may not be available when attempting to enqueue a query with  its
       PGparam  object.   Instead, a PGparam object can used for the sole pur-
       pose of  creating  duplicates  while  there  are  no  available  PGconn
       objects.

       PQparamCount() gets the number of parameters in a PGparam object.

       PQparamReset()  will  clear out any previously put parameters, but will
       not free any memory.  This is useful for application looking to "reuse"
       a PGparam object.

       PQparamClear()  releases  all resources being used by a PGparam object,
       the object should not be used after a clear.

       It is very important to call PQparamReset() if you plan  on  reusing  a
       PGparam object.

RETURN VALUE
       PQparamCreate()  returns  a  pointer to a PGparam object on success and
       NULL if something failed (check PQgeterror(3) for more information).

       PQparamCount() returns the number of parameters in a PGparam object.

       PQparamReset() and PQparamClear() have no  return  values.   If  either
       function is provided a NULL PGparam pointer, it will silently fail.

EXAMPLES
       None.

AUTHOR
       A  contribution  of  eSilo, LLC. for the PostgreSQL Database Management
       System.  Written by Andrew Chernow and Merlin Moncure.

REPORTING BUGS
       Report bugs to <libpqtypes@esilo.com>.

COPYRIGHT
       Copyright (c) 2011 eSilo, LLC. All rights reserved.
       This is free software; see the source for copying conditions.  There is
       NO  warranty; not even for MERCHANTABILITY or  FITNESS FOR A PARTICULAR
       PURPOSE.

SEE ALSO
       pqt-specs(3), PQputf(3), PQgeterror(3), PQparamExec(3)



libpqtypes                           2011                     PQparamCreate(3)

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