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<td><img align="middle" src="../images/green.gif" WIDTH="12" HEIGHT="12"> <A href="Command.html" style="TEXT-DECORATION: none">
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SACommand</A> </FONT> </td>
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SAConnection</A> </FONT> </td>
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SAException</font></A> </td>
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SAField</A> </FONT> </td>
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SAParam</A> </FONT> </td>
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<A href="String.html" style ="TEXT-DECORATION: none" >
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SAString</A> </FONT> </td>
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<A href="DateTime.html" style ="TEXT-DECORATION: none" >
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SADateTime</A> </FONT> </td>
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<td align="left"> <A href="Field.html" style="TEXT-DECORATION: none"><h3>Class Members</h3></A>
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<td align="left"> <A href="Field_Examples.html" style="TEXT-DECORATION: none"><h3>Examples</h3></A>
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<td colspan="2"><h1>SAField object</h1></td>
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<p>A command (an SQL statement or procedure)
can have a result set after executing. If result set exists, a set
of <B>SAField</B> objects is created implicitly. Each <b>SAField</b> object represents a column in
result set.
<p>With the methods of <STRONG>SAField</STRONG>
object you can do the following actions with metadata:</p>
<UL>
<LI>Return the name of a field using <A
href="Field_Name.html">Name</A>
method and field position in
result set using <A href="Field_Pos.html">Pos</A>
method;<BR><BR>
<LI>Return the basic characteristics of a field with the <A
href="Field_FieldType.html">FieldType</A>, <A
href="Field_FieldPrecision.html">FieldPrecision</A>,
and <A
href="Field_FieldScale.html">FieldScale</A> methods;<BR><BR>
<LI>Return the declared size of a field calling <A
href="Field_FieldSize.html">FieldSize</A> method;<BR><BR>
<LI>Check if it is possible for the field value to be null with
<A href="Field_isFieldRequired.html">isFieldRequired</A>
method.</LI></UL>
<P><STRONG>SAField</STRONG> object methods provide the following
possibilities to work with field value:</P>
<UL>
<LI>View the data in the field with the <A
href="Field.html#Methods inherited from SAValueRead">methods
inherited from <STRONG>SAValueRead</STRONG>
class</A>
(<STRONG>asLong</STRONG>, <STRONG>asFloat</STRONG>,
<STRONG>asDouble</STRONG>, <STRONG>asString</STRONG> and so
on);<BR><BR>
<LI>Organize piecewise reading of Long or BLob(CLob) value using <A
href="Field_ReadLongOrLob.html">ReadLongOrLob</A>
method.</LI></UL>
<P>You can not create <STRONG>SAField</STRONG> object by yourself. The Library always does
it implicitly when needed. To get <STRONG>SAField</STRONG> object
use <A href="Command_Field.html">SACommand::Field</A>
method. You can get the
number of fields created calling <A
href="Command_FieldCount.html">SACommand::FieldCount</A>
method.
</P>
<P> All of the metadata field characteristics (field name,
size, type, precision, scale) are available immediately after
<STRONG>SAField</STRONG>
object creating
(generally after command preparing, but on some servers after
command executing). A value of field is
available only after fetching row from a result set (see <A
href="Command_FetchNext.html">SACommand::FetchNext</A> method). </P>
<H3>See also</H3>
<P><A href="Command.html">SACommand</A></P>
<h3>Problems and Questions</h3>
<p> If
you don't find the answer to you questions or
have some problems on using the Library, please, send e-mail to <A href="mailto:howto@sqlapi.com">howto@sqlapi.com</A>.
</p>
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