dbd::oracle.3

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

\&  (SID_LIST =
\&    (SID_DESC =
\&      (SID_NAME = xxxx)
\&      (ORACLE_HOME = /xxx/local/oracle7\-3)
\&        (PRESPAWN_MAX = 40)
\&        (PRESPAWN_LIST=
\&        (PRESPAWN_DESC=(PROTOCOL=tcp) (POOL_SIZE=40) (TIMEOUT=120))
\&      )
\&    )
\&  )
.Ve
.PP
1) When the application is co-located on the host \s-1AND\s0 there is no need for
outside SQLNet connectivity, stop the listener. You do not need it. Get
your application/cgi/whatever working using pipes and shared memory. I am
convinced that this is one of the connection bugs (sockets over the same
machine). Note the \f(CW$ENV\fR{\s-1ORAPIPES\s0} env var.  The essential code to do
this at the end of this section.
.PP
2) Be careful in how you implement the multi-threaded server. Currently I
am not using it in the initxxxx.ora file but will be doing some more testing.
.PP
3) Be sure to create user rollback segments and use them; do not use the
system rollback segments; however, you must also create a small rollback
space for the system as well.
.PP
5) Use large tuning settings and get lots of \s-1RAM\s0. Check out all the
parameters you can set in v$parameters because there are quite a few not
documented you may to set in your initxxx.ora file.
.PP
6) Use svrmgrl to control oracle from the command line. Write lots of small
\&\s-1SQL\s0 scripts to get at V$ info.
.PP
.Vb 11
\&  use DBI;
\&  # Environmental variables used by Oracle
\&  $ENV{ORACLE_SID}   = "xxx";
\&  $ENV{ORACLE_HOME}  = "/opt/oracle7";
\&  $ENV{EPC_DISABLED} = "TRUE";
\&  $ENV{ORAPIPES} = "V2";
\&  my $dbname = "xxx";
\&  my $dbuser = "xxx";
\&  my $dbpass = "xxx";
\&  my $dbh = DBI\->connect("dbi:Oracle:$dbname", $dbuser, $dbpass)
\&             || die "Unable to connect to $dbname: $DBI::errstr\en";
.Ve
.Sh "Oracle utilities"
.IX Subsection "Oracle utilities"
If you are still having problems connecting then the Oracle adapters
utility may offer some help. Run these two commands:
.PP
.Vb 2
\&  $ORACLE_HOME/bin/adapters
\&  $ORACLE_HOME/bin/adapters $ORACLE_HOME/bin/sqlplus
.Ve
.PP
and check the output. The \*(L"Protocol Adapters\*(R" section should be the
same.  It should include at least \*(L"\s-1IPC\s0 Protocol Adapter\*(R" and \*(L"\s-1TCP/IP\s0
Protocol Adapter\*(R".
.PP
If it generates any errors which look relevant then please talk to your
Oracle technical support (and not the dbi-users mailing list). Thanks.
Thanks to Mark Dedlow for this information.
.Sh "Constants"
.IX Subsection "Constants"
.IP ":ora_session_modes" 4
.IX Item ":ora_session_modes"
.Vb 1
\&  ORA_SYSDBA ORA_SYSOPER
.Ve
.IP ":ora_types" 4
.IX Item ":ora_types"
.Vb 4
\&  ORA_VARCHAR2 ORA_STRING ORA_NUMBER ORA_LONG ORA_ROWID ORA_DATE
\&  ORA_RAW ORA_LONGRAW ORA_CHAR ORA_CHARZ ORA_MLSLABEL ORA_NTY
\&  ORA_CLOB ORA_BLOB ORA_RSET ORA_VARCHAR2_TABLE ORA_NUMBER_TABLE
\&  SQLT_INT SQLT_FLT
.Ve
.IP "\s-1SQLCS_IMPLICIT\s0" 4
.IX Item "SQLCS_IMPLICIT"
.PD 0
.IP "\s-1SQLCS_NCHAR\s0" 4
.IX Item "SQLCS_NCHAR"
.PD
\&\s-1SQLCS_IMPLICIT\s0 and \s-1SQLCS_NCHAR\s0 are \fIcharacter set form\fR values.
See notes about Unicode elsewhere in this document.
.IP "\s-1SQLT_INT\s0" 4
.IX Item "SQLT_INT"
.PD 0
.IP "\s-1SQLT_FLT\s0" 4
.IX Item "SQLT_FLT"
.PD
These types are used only internally, and may be specified as internal
bind type for \s-1ORA_NUMBER_TABLE\s0. See notes about \s-1ORA_NUMBER_TABLE\s0 elsewhere
in this document
.IP "\s-1ORA_OCI\s0" 4
.IX Item "ORA_OCI"
Oracle doesn't provide a formal \s-1API\s0 for determining the exact version
number of the \s-1OCI\s0 client library used, so DBD::Oracle has to go digging
(and sometimes has to more or less guess).  The \s-1ORA_OCI\s0 constant
holds the result of that process.
.Sp
In string context \s-1ORA_OCI\s0 returns the full \*(L"A.B.C.D\*(R" version string.
.Sp
In numeric context \s-1ORA_OCI\s0 returns the major.minor version number
(8.1, 9.2, 10.0 etc).  But note that version numbers are not actually
floating point and so if Oracle ever makes a release that has a two
digit minor version, such as \f(CW9.10\fR it will have a lower numeric
value than the preceding \f(CW9.9\fR release. So use with care.
.Sp
The contents and format of \s-1ORA_OCI\s0 are subject to change (it may,
for example, become a \fIversion object\fR in later releases).
I recommend that you avoid checking for exact values.
.Sh "Connect Attributes"
.IX Subsection "Connect Attributes"
.IP "ora_session_mode" 4
.IX Item "ora_session_mode"
The ora_session_mode attribute can be used to connect with \s-1SYSDBA\s0
authorization and \s-1SYSOPER\s0 authorization.
The \s-1ORA_SYSDBA\s0 and \s-1ORA_SYSOPER\s0 constants can be imported using
.Sp
.Vb 1
\&  use DBD::Oracle qw(:ora_session_modes);
.Ve
.Sp
This is one case where setting \s-1ORACLE_SID\s0 may be useful since
connecting as \s-1SYSDBA\s0 or \s-1SYSOPER\s0 via SQL*Net is frequently disabled
for security reasons.
.Sp
Example:
.Sp
.Vb 3
\&  $dsn = "dbi:Oracle:";       # no dbname here
\&  $ENV{ORACLE_SID} = "orcl";  # set ORACLE_SID as needed
\&  delete $ENV{TWO_TASK};      # make sure TWO_TASK isn\*(Aqt set
\&
\&  $dbh = DBI\->connect($dsn, "", "", { ora_session_mode => ORA_SYSDBA });
.Ve
.Sp
It has been reported that this only works if \f(CW$dsn\fR does not contain a \s-1SID\s0
so that Oracle then uses the value of the \s-1ORACLE_SID\s0 (not \s-1TWO_TASK\s0)
environment variable to connect to a local instance. Also the username
and password should be empty, and the user executing the script needs
to be part of the dba group or osdba group.
.IP "ora_oratab_orahome" 4
.IX Item "ora_oratab_orahome"
Passing a true value for the ora_oratab_orahome attribute will make
DBD::Oracle change \f(CW$ENV\fR{\s-1ORACLE_HOME\s0} to make the Oracle home directory
specified in the \f(CW\*(C`/etc/oratab\*(C'\fR file \fIif\fR the database to connect to
is specified as a \s-1SID\s0 that exists in the oratab file, and DBD::Oracle was
built to use the Oracle 7 \s-1OCI\s0 \s-1API\s0 (not Oracle 8+).
.IP "ora_module_name" 4
.IX Item "ora_module_name"
After connecting to the database the value of this attribute is passed
to the \s-1\fISET_MODULE\s0()\fR function in the \f(CW\*(C`DBMS_APPLICATION_INFO\*(C'\fR \s-1PL/SQL\s0
package. This can be used to identify the application to the \s-1DBA\s0 for
monitoring and performance tuning purposes. For example:
.Sp
.Vb 1
\&  DBI\->connect($dsn, $user, $passwd, { ora_module_name => $0 });
.Ve
.IP "ora_dbh_share" 4
.IX Item "ora_dbh_share"
Needs at least Perl 5.8.0 compiled with ithreads. Allows to share database
connections between threads. The first connect will make the connection, 
all following calls to connect with the same ora_dbh_share attribute
will use the same database connection. The value must be a reference
to a already shared scalar which is initialized to an empty string.
.Sp
.Vb 1
\&  our $orashr : shared = \*(Aq\*(Aq ;
\&
\&  $dbh = DBI\->connect ($dsn, $user, $passwd, {ora_dbh_share => \e$orashr}) ;
.Ve
.IP "ora_use_proc_connection" 4
.IX Item "ora_use_proc_connection"
This attribute allows to create a \s-1DBI\s0 handle for an existing \s-1SQLLIB\s0
database connection. This can be used to share database connections
between Oracle ProC code and \s-1DBI\s0 running in an embedded Perl interpreter.
The \s-1SQLLIB\s0 connection id is appended after the \*(L"dbi:Oracle:\*(R" initial
argument to DBI::connect.
.Sp
For example, if in ProC a connection is made like
.Sp
.Vb 1
\&    EXEC SQL CONNECT \*(Aquser/pass@db\*(Aq AT \*(AqCONID\*(Aq;
.Ve
.Sp
the connection may be used from \s-1DBI\s0 after running something like
.Sp
.Vb 2
\&    my $dbh = DBI\->connect("dbi:Oracle:CONID", "", "",
\&                           { ora_use_proc_connection => 1 });
.Ve
.Sp
To disconnect, first call \f(CW$dbh\fR\->\fIdisconnect()\fR, then disconnect in ProC.
.Sp
This attribute requires DBD::Oracle to be built with the \-ProC
option to Makefile.PL.  It is not available with \s-1OCI_V7\s0. Not tested
with Perl ithreads or with the ora_dbh_share connect attribute.
.IP "ora_envhp" 4
.IX Item "ora_envhp"
The first time a connection is made a new \s-1OCI\s0 'environment' is
created by DBD::Oracle and stored in the driver handle.
Subsequent connects reuse (share) that same \s-1OCI\s0 environment
by default.
.Sp
The ora_envhp attribute can be used to disable the reuse of the \s-1OCI\s0
environment from a previous connect. If the value is \f(CW0\fR then
a new \s-1OCI\s0 environment is allocated and used for this connection.
.Sp
The \s-1OCI\s0 environment is what holds information about the client side
context, such as the local \s-1NLS\s0 environment. So by altering \f(CW%ENV\fR and
setting ora_envhp to 0 you can create connections with different
\&\s-1NLS\s0 settings. This is most useful for testing.
.IP "ora_charset, ora_ncharset" 4
.IX Item "ora_charset, ora_ncharset"
For oracle versions >= 9.2 you can specify the client charset and
ncharset with the ora_charset and ora_ncharset attributes.  You
still need to pass \f(CW\*(C`ora_envhp = 0\*(C'\fR for all but the first connect.
.Sp
These attributes override the settings from environment variables.
.Sp
.Vb 2
\&  $dbh = DBI\->connect ($dsn, $user, $passwd,
\&                       {ora_charset => \*(AqAL32UTF8\*(Aq});
.Ve
.Sh "Database Handle Attributes"
.IX Subsection "Database Handle Attributes"
.ie n .IP """ora_ph_type""" 4
.el .IP "\f(CWora_ph_type\fR" 4
.IX Item "ora_ph_type"
The default placeholder data type for the database session.
The \f(CW\*(C`TYPE\*(C'\fR or \*(L"ora_type\*(R" attributes to \*(L"bind_param\*(R" in \s-1DBI\s0 and
\&\*(L"bind_param_inout\*(R" in \s-1DBI\s0 override the data type for individual placeholders.
The most frequent reason for using this attribute is to permit trailing spaces
in values passed by placeholders.
.Sp
Constants for the values allowed for this attribute can be imported using
.Sp
.Vb 1
\&  use DBD::Oracle qw(:ora_types);
.Ve
.Sp
Only the following values are permitted for this attribute.
.RS 4
.IP "\s-1ORA_VARCHAR2\s0" 4
.IX Item "ORA_VARCHAR2"
Oracle clients using \s-1OCI\s0 8 will strip trailing spaces and allow embedded \e0 bytes.
Oracle clients using \s-1OCI\s0 9.2 do not strip trailing spaces and allow embedded \e0 bytes.
This is the normal default placeholder type.
.IP "\s-1ORA_STRING\s0" 4
.IX Item "ORA_STRING"
Don't strip trailing spaces and end the string at the first \e0.
.IP "\s-1ORA_CHAR\s0" 4
.IX Item "ORA_CHAR"
Don't strip trailing spaces and allow embedded \e0.
Force 'blank\-padded comparison semantics'.
.Sp
For example:
.Sp
.Vb 1
\&  use DBD::Oracle qw(:ora_types);
\&  
\&  $sql="select username from all_users where username = ?";
\&  #username is a char(8)
\&   
\&  $sth=$dbh\->prepare($sql)";
\&   
\&  $sth\->bind_param(1,\*(Aqbloggs\*(Aq,{ ora_type => ORA_CHAR});
.Ve
.Sp
Will pad bloggs out to 8 chracters and return the username.
.RE
.RS 4
.RE
.IP "ora_parse_error_offset" 4
.IX Item "ora_parse_error_offset"
If the previous error was from a failed \f(CW\*(C`prepare\*(C'\fR due to a syntax error,
this attribute gives the offset into the \f(CW\*(C`Statement\*(C'\fR attribute where the
error was found.
.IP "ora_array_chunk_size" 4
.IX Item "ora_array_chunk_size"
Because of \s-1OCI\s0 limitations, DBD::Oracle needs to buffer up rows of
bind values in its \f(CW\*(C`execute_for_fetch\*(C'\fR implementation. This attribute
sets the number of rows to buffer at a time (default value is 1000).
.Sp
The \f(CW\*(C`execute_for_fetch\*(C'\fR function will collect (at most) this many
rows in an array, send them of to the \s-1DB\s0 for execution, then go back
to collect the next chunk of rows and so on. This attribute can be
used to limit or extend the number of rows processed at a time.
.Sp
Note that this attribute also applies to \f(CW\*(C`execute_array\*(C'\fR, since that
method is implemented using \f(CW\*(C`execute_for_fetch\*(C'\fR.
.Sh "Prepare Attributes"
.IX Subsection "Prepare Attributes"
These attributes may be used in the \f(CW\*(C`\e%attr\*(C'\fR parameter of the
\&\*(L"prepare\*(R" in \s-1DBI\s0 database handle method.
.IP "ora_placeholders" 4
.IX Item "ora_placeholders"
Set to false to disable processing of placeholders. Used mainly for loading a
\&\s-1PL/SQL\s0 package that has been \fIwrapped\fR with Oracle's \f(CW\*(C`wrap\*(C'\fR utility.
.IP "ora_parse_lang" 4
.IX Item "ora_parse_lang"
Tells the connected database how to interpret the \s-1SQL\s0 statement.
If 1 (default), the native \s-1SQL\s0 version for the database is used.
Other recognized values are 0 (old V6, treated as V7 in \s-1OCI8\s0),
2 (old V7), 7 (V7), and 8 (V8).
All other values have the same effect as 1.
.IP "ora_auto_lob" 4
.IX Item "ora_auto_lob"
If true (the default), fetching retrieves the contents of the \s-1CLOB\s0 or
\&\s-1BLOB\s0 column in most circumstances.  If false, fetching retrieves the
Oracle \*(L"\s-1LOB\s0 Locator\*(R" of the \s-1CLOB\s0 or \s-1BLOB\s0 value.
.Sp
See \*(L"Handling LOBs\*(R" for more details.
See also the \s-1LOB\s0 tests in 05dbi.t of Oracle::OCI for examples
of how to use \s-1LOB\s0 Locators.
.IP "ora_check_sql" 4
.IX Item "ora_check_sql"
If 1 (default), force \s-1SELECT\s0 statements to be described in \fIprepare()\fR.
If 0, allow \s-1SELECT\s0 statements to defer describe until \fIexecute()\fR.
.Sp
See \*(L"Prepare postponed till execute\*(R" for more information.
.Sh "Placeholder Binding Attributes"
.IX Subsection "Placeholder Binding Attributes"
These attributes may be used in the \f(CW\*(C`\e%attr\*(C'\fR parameter of the
\&\*(L"bind_param\*(R" in \s-1DBI\s0 or \*(L"bind_param_inout\*(R" in \s-1DBI\s0 statement handle methods.
.IP "ora_type" 4
.IX Item "ora_type"
Specify the placeholder's data type using an Oracle data type.
A fatal error is raised if \f(CW\*(C`ora_type\*(C'\fR and the \s-1DBI\s0 \f(CW\*(C`TYPE\*(C'\fR attribute
are used for the same placeholder.
Some of these types are not supported by the current version of
DBD::Oracle and will cause a fatal error if used.