Sadly, while in a perfect world Boolean is stored as one bit, apparently it doesn't happen that way: according to discussion at <a href="http://www.access-programmers.co.uk/forums/showthread.php?t=152490">http://www.access-programmers.co.uk/forums/showthread.php?t=152490</a> Boolean in Access is stored (like Filemaker does) as an integer: 2 entire bytes! <br>
<br>So it seems that the space-saving glory of Boolean is a bit of false advertising...<br><br><div class="gmail_quote">On 5 April 2011 20:14, Timmer-Arends <span dir="ltr"><<a href="mailto:timmer@melbpc.org.au">timmer@melbpc.org.au</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div vlink="purple" link="blue" bgcolor="white" lang="EN-AU">
<div><font face="Arial" size="2">Hello Mark K and Matt</font></div>
<div><font face="Arial" size="2"></font> </div>
<div><font face="Arial" size="2">1. </font>So Access doesn't have a true Boolean
datatype.... and neither does Filemaker (one uses a number field with values of
non-zero or 0). Which RDBMS <b>does</b> have a fair dinkum native Boolean
datatype?</div>
<div><font face="Arial" size="2"></font> </div>
<div><font face="Arial" size="2">Access does have a "fair dinkum" Boolean data type
- it's a 1 bit field and that means it can be either 0 or 1 and you can't get
much more Boolean than that. Null is not allowed. As the setter-upper of the db
you can choose a number of ways to display it, the default being
yes/no.</font><br><span style="font-size:11pt;color:#1f497d"></span></div>
<div><span style="font-size:11pt;color:#1f497d"><font face="Arial"><font size="2">2. I always thought Boolean operators
were:</font></font></span></div>
<div class="MsoNormal" style="margin-left:72pt"><span style="font-size:11pt;color:#1f497d"><font face="Arial"><font size="2">NOT</font></font></span></div>
<div class="MsoNormal" style="margin-left:72pt"><span style="font-size:11pt;color:#1f497d"><font face="Arial"><font size="2">OR</font></font></span></div>
<div class="MsoNormal" style="margin-left:72pt"><span style="font-size:11pt;color:#1f497d"><font face="Arial"><font size="2">AND</font></font></span></div>
<div class="MsoNormal"><span style="font-size:11pt;color:#1f497d"><font face="Arial"><font size="2">Thus in the sample paper M / F the Boolean operator
would OR?</font></font></span></div>
<div class="MsoNormal"><span style="font-size:11pt;color:#1f497d"><font face="Arial"><font size="2"></font></font></span> </div>
<div class="MsoNormal"><span style="font-size:11pt;color:#1f497d"><font color="#000000" face="Arial" size="2">But the question doesn't ask about operator (or
have I missed something?). It asks about data type and I agree with other
comments: F/M is the only possible answer because it's a two value field, but I
wouldn't have thought it would be a good idea for a number of reasons including
every time you want to display it you have to do an IF operation
(IF(gender,"Female","Male") or something), also, in Access at least, NULL would
not be allowed and I can think of circumstances where this would a be valid
entry (for example, maybe we just don't know, in which case NULL would be more
valid than a forced True or False)</font></span></div>
<div class="MsoNormal"><span style="font-size:11pt;color:#1f497d"><font color="#000000" face="Arial" size="2"></font></span> </div>
<div class="MsoNormal"><span style="font-size:11pt;color:#1f497d"></span> </div></div>
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