📄 otl3_whatn_3.htm
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<title>Oracle, Odbc and DB2-CLITemplate Library, Version 3.2, What's New</title>
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<h1>
Oracle, Odbc and DB2-CLI Template Library, Version 3.2</h1></center>
<center>
<h1>
What's New</h1></center>
<h1>
Rlogon() and otl_connect() constructor were enhanced with the auto_commit
parameter</h1>
For more detail, see the <a href="otl3_connect_class.htm#rlogon">rlogon</a>()
function and examples <a href="otl3_ex46.htm">46,</a> <a href="otl3_ex47.htm">47</a>,
<a href="otl3_ex48.htm">48</a>.
<b><i>The
<a href="otl4_htm.zip">archived version</a> of the OTL Programmer's Guide was
updated.</i></b>
<br>
<br>
<h1>
direct_exec() now returns a rows processed count; otl_stream::get_rpc()
was added, it returns a rows processed count</h1>
For more detail, see <a href="otl3_stream_class.htm#get_rpc">get_rpc</a>(),
<a href="otl3_const_sql.htm">direct_exec</a>(),
and examples <a href="otl3_ex43.htm">43</a>,
<a href="otl3_ex44.htm">44</a>,
<a href="otl3_ex45.htm">45</a>.
<b><i>The
<a href="otl4_htm.zip">archived version</a> of the OTL Progermmer's Guide was updated.</i></b>
<br>
<h1>
OTL namespaces have been streamlined in OTL 3.1.30</h1>
For more detail, see <a href="otl3_namespaces.htm">OTL namespaces</a> and
<a href="otl3_ex42.htm">example
42</a>.
<br>
<h1>
Example 42 was added to demonstrate how to use more than one instance of
OTL (e.g. OTL/ODBC and OTL/OCI8) and OTL namespaces</h1>
In order to see the example, click <a href="otl3_ex42.htm">here</a>. This
new example demonstrates how to connect to both MS SQL Server and Oracle
8, creates tables in both, fill out the source table in MS SQL, and then
copy it over to the target table in Oracle 8. Click <a href="otl3_namespaces.htm">here
</a>for
more detail on the OTL namespaces. <b><i>The <a href="otl4_htm.zip">archived version
</a> of the OTL Programmer's was updated.</i></b>
<br>
<h1>
Example 41 was added to the list of examples in order to demonstrate how
to do UPDATEs with CLOBs in Oracle 8</h1>
In order to see the example, click <a href="otl3_ex41.htm">here</a>. This
new example demonstrates UPDATEs with CLOBs in Oracle 8. UPDATEs with BLOBs
are similar to the UPDATEs with CLOBs if the word clob is replaced with
the word blob. Also, <b><i>the <a href="otl4_htm.zip">archived version</a>
of the OTL Progermmer's Guide was updated.</i></b>
<br>
<h1>
OTL Header file is available for download</h1>
In order to dowload the OTL header file, click <a href="otlv4_h.zip">here</a>.
<br>
<h1>
OTL Programmer's Guide is available in the archived format for download</h1>
In order to dowload the OTL Programmer's Guide, click <a href="otl4_htm.zip">here</a>.
<br>
<h1>
OTL 3.0.26 in comparsion with OTL 3.0.20</h1>
In this release, a new data container was introduced: <a href="otl3_stream_class.htm#otl_datetime">otl_datetime</a>..
For more detail, see examples <a href="otl3_ex38.htm">38</a>, <a href="otl3_ex39.htm">39</a>
and <a href="otl3_ex40.htm">40</a>. Otl_datetime is unified for both OCIx
and ODBC, meaning that it can be used uniformly across the board.
<p><i>NOTE. </i>Important change in the OTL behavior: Oracle DATE [table]
columns do not get mapped to the string variables any longer. They get
mapped to the Oracle internal [7-byte] date format and can be read/written
with the use otl_datetime variables. If need be, Oracle DATE has to be
converted into the string format and back expilcitly with the help of TO_CHAR()
and TO_DATE() functions, directly in SQL statements or PL/SQL blocks.
<h1>
OTL 3.0.20 in comparsion with OTL 3.0.19</h1>
In this release, a major effort was made to clean up as many compilation
warnings as possible, to make OTL compilable at the level of C++ compiler
warnings set to its maximum: typical warnings like unused arguments in
function, typecasting, missing assigment operators or copy constructors,
etc. Also, examples <a href="otl3_ex35.htm">35</a>, <a href="otl3_ex36.htm">36</a>
and <a href="otl3_ex37.htm">37</a> were added to the list of OTL examples
in order to demonstrate the use of the <a href="otl3_stream_class.htm#nocommit">otl_nocommit_stream</a>
class.
<h1>
<a NAME="ODBC30"></a>OTL 3.0.19 in comparsion with OTL 3.0.16</h1>
In this release, OTL 3.1/ODBC was made compliant with the ODBC 3.x specification.
In other words, older (ODBC 2.x) function calls were replaced with ODBC
3.x function calls, to straighten out the behavior of OTL 3.1/ODBC when
it's connected to MS SQL Server 7.0. This is really an internal enchance
of the library.
<br>
<br>
<h1>
OTL 3.0.16 in comparsion with OTL 3.0.0</h1>
In this release, a new class was introduced: <font size=+2><a href="otl3_stream_class.htm#nocommit">otl_nocommit_stream</a></font><font size=+1>.
</font>This
class is a derivative of the otl_stream class. otl_nocommit_stream supports
all features, supported by otl_stream, but it hehaves differently. otl_nocommit_stream
does not commit transactions, as apposed to otl_stream that commits transactions
by default.
<h1>
OTL 3.0 in comparison with OTL 2.x <font size=+1>(updated 11/20/1999)</font></h1>
This version of the OTL is compatible with the OTL/ODBC 2.x and OTL/OCI
2.x series when <a href="otl3_stream_class.htm">otl_stream</a>'s, <a href="otl3_connect_class.htm">otl_connect</a>'s
and <a href="otl3_exception_class.htm">otl_exception</a>'s are used. Support
of low level features has been discontinued in this version.
<p>The OTL 2.x/ODBC as well as OTL 2.x/OCI had the STL compliant otl_stream
<a href="Otl_it02.htm">input</a>
and <a href="Otl_it01.htm">output</a> iterators. Because of the low demand
(I recevied too few requests on that) this feature has been discontinued.
The iterators are based on the <a href="http://www.sgi.com/Technology/STL/">SGI
STL</a>. The old <i>otl_iter.h </i>header file can be used with the OTL
3.0, though.
<p>The main difference between the OTL 3.1 and the OTL 2.x releases is
that the OTL/OCI 2.x and the OTL/ODBC 2.x were integrated into a single
library. A new, completely templatized framework was developed. Also, a
series of so called OTL-adaptors was developed for the following database
API's:
<ul>
<li>
Oracle Call Interface 7 (OCI7)</li>
<li>
Oracle Call Interface 8 (OCI8)</li>
<li>
Open DataBase Connectivity (ODBC)</li>
</ul>
A complete set of functions was developed to manipulate with Large Object
(LOB) columns. In particular, the following datatypes are supported:
<ul>
<li>
MS SQL TEXT and IMAGE</li>
<li>
Sybase TEXT and IMAGE</li>
<li>
Oracle 7 LONG and LONG RAW</li>
<li>
LONG and LONG RAW in Oracle 8 as well as CLOB and BLOB</li>
</ul>
In <a href="otl3_exception_class.htm">otl_exception</a>, a new field was
introduced:
<pre> char var_info[256]</pre>
It contains variable specific information in case if the following otl_exception
is raised in the otl_stream operators >> or <<: "Incompatible datatypes
in stream operation." It is useful when debugging operations with otl_streams.
The <i>var_info </i>field provides a placeholder name (say, in an INSERT
statement) or a relative number of an output column in a SELECT statement.
Also, the <i>var_info</i> provides information on both the datatype of
the placeholder/output column and the datatype of the actual parameter
in the otl_stream operator to be used.
<p><i>stm_text</i> is no longer a char* pointer, it was replaced with the
straight char <i>stm_text[2048]</i> array. First 2047 bytes of a SQL statement
are copied over from an otl_stream (or constant statement) into the <i>stm_text</i>
container.
<p>In the OTL 3.1 instantiated from the template framework and the OTL-adaptor
for ODBC (OTL 3.0/ODBC for short), a new <a href="otl3_bind_variables.htm">placeholder
notation</a> is supported, similar to Oracle type style placeholders:
<pre> "INSERT INTO test_tab VALUES(:<b>f1</b><int>,:<b>f2</b><char[33]>)"</pre>
In the OTL 2.x for ODBC, the placeholder notation was a little bit different:
<pre> "INSERT INTO test_tab VALUES(:<b>1</b><int>,:<b>2</b><char[33]>)"</pre>
It is still possible to use the old notation in OTL3.0/ODBC but it is recommended
to use the new placeholder notation since it is compatibel with the placeholder
notation for OTL3.0/OCIx. It will make source code more portable across
databases.
<p>The only limitation on the new style ODBC placeholders is that it is
not allowed to refer to the same placeholder in a SQL statement more than
once. For example, the following SQL statement works in the OTL 3.0/OCI
but it does not work in the OTL 3.0/ODBC:
<pre> "SELECT * "
"FROM test_tab "
"WHERE f1>=:<b>f1</b><int> "
" AND f1<=:<b>f1</b>*2 "</pre>
In the OTL 3.0/ODBC, it needs to be rewritten this way:
<pre> "SELECT * "
"FROM test_tab "
"WHERE f1>=:<b>f11</b><int> "
" AND f1<=:<b>f12</b><int>*2 "</pre>
This is necessary in order to make each placeholder unique. This limitation
is actually imposed by the ODBC standard. Placeholders in ODBC are positional,
for example:
<pre> "SELECT * "
"FROM test_tab "
"WHERE f1>= <b>?</b> "
" AND f1<= <b>?</b> * 2 "</pre>
So, the first question mark in the statement above is placeholder number
1. The second question mark is placeholder number 2.
<p>Several new functions were introduced in the otl_stream and <a href="otl3_connect_class.htm">otl_connect</a>
classes. For example, in the OTL 3.0/ODBC:
<pre> db.set_timeout(<X seconds>);</pre>
This function sets a timeout on a connect object. The function has no effect
in the OTL 3.0/OCI. It works with ODBC only. If, in the future, OCI provides
client side timeout functionality, the function will have an actual implementation.
<p>See the <a href="otl3.htm">OTL 3.0 manual</a> or more detail.
<h2>
How to compile OTL 3.0</h2>
The following macro definitions (#define's) need to be defined in order
to <a href="otl3_compile.htm">instantiate</a> different implementations
of the OTL 3.0:
<ul>
<li>
<b>OTL_ODBC</b> (for ODBC)</li>
<li>
<b>OTL_ORA7</b> (for OCI7)</li>
<li>
<b>OTL_ORA8</b> (for OCI8)</li>
</ul>
<h2>
New namespace naming convensions</h2>
By default, there is no <a href="otl3_namespaces.htm">namespace</a> defined
in the OTL 3.0. If need be, each instantiation (OCI7, OCI8 or ODBC) of
the OTL 3.0 can be wrapped up with a separate namespace. See the OTL header
file for more detail.
<h2>
New data container for Large Objects</h2>
<i><a href="otl3_long_string.htm">otl_long_string</a></i> class was introduced
in the OTL 3.0 to hold Large Object values: TEXT's, IMAGE's, LONG's, LONG
RAW's, CLOB's, BLOB's. The OTL 2.1/ODBC had the <i>otl_long_string
</i>class
but in the OTL 3.0 the class was generalized to contain any Large Objects
<p>Two new <a href="otl3_bind_variables.htm">placeholder datatypes</a>
were introduced:
<ul>
<li>
<i>varchar_long</i> (to declare TEXT (MS SQL, Sybase), LONG (Oracle 7/8)
variables)</li>
<li>
<i>raw_long</i> (to declare IMAGE (MS SQL, Sybase), LONG RAW (Oracle 7/8)
variables)</li>
<li>
<i>clob </i>(to declare CLOB (Oracle 8) variables)</li>
<li>
<i>blob </i>(to declare BLOB (Oracle 8) variables)</li>
</ul>
See <a href="otl3.htm">the OTL 3.0 manual</a> and the header file for more
detail.
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<p>Copyright © 1996, 2008, Sergei Kuchin, email: <a href="mailto:skuchin@aceweb.com">skuchin@aceweb.com</a>,
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