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Working with date/time values</A> </FONT> </td>
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<h1>Working with date/time values</h1>
</center>
<P>Working with date/time values assumes the
following:</P>
<UL>
<LI><A href="#Binding date/time values" >Binding date/time values</A> into
input variables (SQL statements) or input parameters (stored
procedures/functions).
<LI><A href="#Reading date/time values" >Reading date/time values</A> (from
fields in result set or from output parameters of stored
procedure)</LI></UL>
<A name="Binding date/time values"></A>
<H4>Binding date/time values</H4>
<P>
Suppose, we want to update date/time field named FDATETIME from
table named TEST (<EM> Update
TEST set FDATETIME = :1 </EM> ) with the
value of October 6, 2000 19:00:00.</P>
<P>As usual, the first thing to do is to create
the objects.<BR><STRONG><FONT face="" size=2><FONT face=System
><FONT size=+0>
SACommand cmd(&Connection, "Update TEST set FDATETIME
= :1");<BR></FONT></FONT></FONT></STRONG>
</P>
<P> Next step is used to actually
bind the date/time value into input variable:<BR><STRONG>SADateTime dtValue( <BR> 2000
/*year*/, 10 /*October*/, 6 /*day of month*/, <BR>
19 /*hours*/, 0 /*minutes*/, 0 /*seconds*/);<BR></STRONG>or (using C
struct tm):<BR><STRONG>extern struct tm
some_tm_Value;<BR><STRONG>SADateTime dtValue =
some_tm_Value;<BR></STRONG></STRONG>or (using Windows DATE data
type):<BR><STRONG>extern DATE
some_DATE_Value;<BR><STRONG>SADateTime dtValue
= some_DATE_Value;</STRONG>
<BR>Next line
binds date/time value.<BR><STRONG>cmd << dtValue;<BR
></STRONG>
</P>
<P>All that we need now is to execute a
query:<BR><STRONG>cmd.Execute();</STRONG> </P>
<A name="Reading date/time values"></A>
<H4>Reading date/time values</H4>
<P>Suppose, we want to retrieve date/time field
named FDATETIME from table named TEST (<EM>Select FDATETIME from
TEST<
/EM >
).</P>
<P>As usual, the first thing to do is to create
the objects:<BR><STRONG><FONT face="" size=2><FONT face=System
><FONT size=+0>
SACommand cmd(&Connection, "Select FDATETIME from
TEST");</FONT></FONT></FONT></STRONG><FONT size=+0><FONT face=System></FONT></FONT> <BR
>F
<A name="Reading Long or Lob data">or more information see </A><A href="connect.html" >Connecting to
databases</A><A name="Reading Long or Lob data">.</A> </P>
<P>Next thing to do is to execute a query:<BR
><STRONG>cmd.Execute();</STRONG> </P>
<P>Next step is used to actually fetch the row
and access date/time data:<BR><STRONG>if(cmd.FetchNext()) // or while(cmd.FetchNext())<BR
>{<BR> SADateTime dtValue =
cmd.Field("FDATETIME");<BR
> // access through standard C struct
tm<BR> struct tm tmValue = dtValue;<BR>
struct tm tmValue2 = (struct
tm)cmd.Field("FDATETIME").asDateTime();<BR>
...<BR> // access through Windows DATE data
type<BR> DATE dateValue = dtValue;<BR> DATE
dateValue2 =
(DATE)cmd.Field("FDATETIME").asDateTime();<BR>
...<BR
>}</STRONG> </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>
<p> </p>
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