sqlbase.html

能够连接各种数据库的API

            <STRONG>SQLBase</STRONG> server in the following way:</P>
            <P> <STRONG 
            >SA_ReadUncommitted</STRONG> = SQLILRL    
            ('RL')<BR><STRONG> SA_ReadCommitted</STRONG> = 
  
  SQLILCS  
              
             ('CS')<BR><STRONG> SA_RepeatableRead</STRONG> = SQLILRR     
            ('RR')<BR><STRONG> SA_Serializable</STRONG> = 
  
  SQLILRO    
              
            ('RO')</P>
            <P>For more details see <A 
            href="../OnLineDoc/Connection_setIsolationLevel.html">SAConnection::setIsolationLevel</A>.</P>
            <P>&nbsp;</P>
            
            <H3><A 
            name="Working with Long or Lob(CLob, BLob) data">Working with Long or Lob(CLob, 
            BLob) data</A>    </H3>
            <P> 
            SQLAPI++ supports four types for working with 
            Long or Lob(CLob, BLob) data:</P>
            <P>
            <TABLE border=1 cellPadding=1 cellSpacing=1 style="WIDTH: 100%" 
            width=100%>
                
                <TR bgColor=navy>
                    <TD><FONT color=white 
                        style="BACKGROUND-COLOR: #000080">Name</FONT></TD>
                    <TD><FONT color=white 
                        style="BACKGROUND-COLOR: #000080">C 
                        enum constant</FONT></TD>
                </TR>
                <TR>
                    <TD>LongBinary</TD>
                    <TD>SA_dtLongBinary</TD>
                </TR>
                <TR>
                    <TD>LongChar</TD>
                    <TD>SA_dtLongChar</TD>
                </TR>
                <TR>
                    <TD>BLob (Binary Large object)</TD>
                    <TD>SA_dtBLob</TD>
                </TR>
                <TR>
                    <TD>CLob (Character Large object)</TD>
                    <TD>SA_dtCLob</TD>
                </TR></TABLE></P>
            <P>The table below shows how SQLAPI++ data 
            types correspond with servers original data types:</P>
            <P><EM>SA_dtLongBinary</EM> &lt;=  &gt;  LONG VARCHAR<BR><EM>SA_dtLongChar</EM> 
            &lt;=  
            &gt;  LONG VARCHAR<BR 
            ><EM>SA_dtBLob</EM> =  &gt;  LONG 
            VARCHAR<BR><EM>SA_dtCLob 
            </EM>=&gt; LONG VARCHAR</EM></P>
            <P>
            For more details see <A href="../HowTo/blobs.html">How To - Working with Long or Lob(CLob, BLob) data</A></P>
            <P>&nbsp;</P>
            
            <H3><A 
            name="Returning output parameters">Returning output 
            parameters</A>  </H3>
            <p>If <STRONG>SQLBase</STRONG>
            stored procedure returns only 
            one row of output parameters (the most common case), you can 
            get output parameters' values immediately after calling 
            <A href="../OnLineDoc/Command_Execute.html">SACommand::Execute</A>
            using appropriate <A href="../OnLineDoc/Param.html">SAParam</A> 
            objects.</p>
            <P>       
                       
             In <STRONG>SQLBase</STRONG>
             stored procedures can also return 
            several rows of output parameters. In this case      
                      SQLBase 
            returns them as a result set and you can 
            fetch them row by row using <A 
            href="../OnLineDoc/Command_FetchNext.html">SACommand::FetchNext</A>
             method after calling 
            <A href="../OnLineDoc/Command_Execute.html">SACommand::Execute</A>          
            method.</P>
            <P>For more details see <A 
            href="../OnLineDoc/Command_Execute.html" >SACommand::Execute</A>, 
            <A href="../OnLineDoc/Param_Usage.html" >SAParam 
            object</A>, <A 
            href="../HowTo/return_param.html" >How To - Returning Output Parameters</A>.</P>
            <P>&nbsp;</P>
            
            <H3><A name="Cancelling queries">Cancelling 
            queries</A> </H3>
            <P>Using <A href="../OnLineDoc/Command_Cancel.html" >SACommand::Cancel</A> method you 
            can cancel the following types of processing on a statement:</P>
            <UL type=disc>
                <LI>A function running asynchronously on 
                the statement.<BR>
                <LI>A function running on the statement on 
                another thread. </LI></UL>
            <p>SQLAPI++ calls <STRONG>sqlcan</STRONG> function to cancel a query. To get more details 
            see <STRONG>sqlcan</STRONG> function 
            description in <STRONG>SQLBase</STRONG>   
              documentation.</p>
            <P>For more details see <A href="../OnLineDoc/Command_Cancel.html" >SACommand::Cancel</A>.</P>
            <P>&nbsp;</P>
            
            <H3><A 
            name="Connection and command options">Connection, command, parameter and field 
            options</A>   </H3>
            <P>A server specific option can relate to a 
            connection, command,&nbsp; parameter or field. We recommend you 
            specify each option in an appropriate object, although it is 
            possible to specify them in the parental object as well. In that 
            case the option affects all the child objects. </P>
            <P>A connection related option must be specified 
            in a&nbsp; <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object. </P>
            <P>A command related option may be specified in 
            either <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object or <A href="../OnLineDoc/Command.html">SACommand</A> 
            object. If it is specified 
            in <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object it affects all 
            the commands on that connection. </P>
            <P>A parameter related option may be specified in 
            <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object, <A href="../OnLineDoc/Command.html">SACommand</A> 
            object or <A href="../OnLineDoc/Param.html">SAParam</A> 
            object. If it is specified in <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object it affects all 
            the commands and therefore all the parameters on that connection. If 
            it is specified in <A href="../OnLineDoc/Command.html">SACommand</A> 
            object it affects all the 
            parameters on that command. </P>
            <P>A field related option may be specified in 
            <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object, <A href="../OnLineDoc/Command.html">SACommand</A> 
            object or <A href="../OnLineDoc/Field.html">SAField</A> 
            object. If it is specified in 
            <A href="../OnLineDoc/Connection.html">SAConnection</A> 
            object it affects all 
            the commands and therefore all the fields on that connection. If it 
            is specified in <A href="../OnLineDoc/Command.html">SACommand</A> 
            object it affects all the 
            fields on that command. </P>
            <P>Specific options for <STRONG> SQLBase</STRONG>:</P>
            <P>
            <TABLE border=1 cellPadding=5 width=100%>
                <TBODY>
                <TR bgColor=#000094>
                    <TD width=17%>
                        <P><STRONG><FONT color=white face="">Option name / Scope</FONT>&nbsp; 
                        </STRONG></P></TD>
                    <TD>
                        <P><STRONG><FONT color=white face=""> Description</FONT> 
                        </STRONG></P></TD></TR>
                <TR>
                    <TD>
                        <P align=center>
						<STRONG>       
		                 SQLPPCX  
                        </STRONG></P>
                        <P align=center>
						Command related</P></TD>
			            <TD>
                        <P>Controls cursor-context 
                        preservation. For more information see SQLBase documentation. <BR>
						<BR><EM>Valid values</EM>: 
                        &quot;off&quot; and &quot;on&quot;.
						<BR><EM>Default 
                        value</EM>: see SQLBase documentation.</P></TD></TR>
                <TR>
                    <TD>
                        <P align=center>
			            <STRONG>       
					    StoredObject   
                        </STRONG></P>
                        <P align=center>
			            Command 
                        related&nbsp;</P></TD>
                    <TD>
                        <P>If you call stored command you 
                        can set this option to &quot;Command&quot; value. It 
                        allows SQLAPI++ to optimize stored command execution. <BR>
                          </P>
                        <P><EM>Valid values</EM>: 
                        &quot;Procedure&quot; and &quot;Command&quot;.
						<BR>
						<EM>Default value</EM>: &quot;Procedure&quot;.</P></TD></TR>
                </TBODY>
			</TABLE>
			</P>
            <P>For more details see <A href="../OnLineDoc/Connection_setOption.html" >SAConnection::setOption</A>, 
            <A href="../OnLineDoc/Command_setOption.html">SACommand::setOption</A>, 
            <A href="../OnLineDoc/Field_setOption.html">SAField::setOption</A>, 
            <A href="../OnLineDoc/Param_setOption.html">SAParam::setOption</A>.
            </P>
            <P>&nbsp;</P>
            
            <H3><A 
            name="Getting native SQLBase API">Getting native SQLBase 
            API</A>   </H3>
            <P>You can call client specific API functions 
            which are not directly supported by SQLAPI++ Library. <A 
            href="../OnLineDoc/Connection_NativeAPI.html">SAConnection::NativeAPI</A> 
            method returns a pointer to the set of native API functions 
            available for <STRONG>SQLBase</STRONG>       
             . To use the database API directly you have to downcast 
            this <STRONG>saAPI</STRONG> pointer to the appropriate type and use its 
            implementation-specific members. The following table shows what type 
            cast you have to make and what additional header file you have to 
            include to work with <STRONG>SQLBase</STRONG>
            API. Note that using appropriate type casting depends 
            on an API version (that generally mean that you have to explicitly 
            check client version before casting, see <A 
            href="../OnLineDoc/Connection_ClientVersion.html">SAConnection::ClientVersion</A> 
            method). </P>
            <P>
            <TABLE border=1 cellPadding=5 width=100%>