The

full outer join has 6 tuples

The

full outer join has 2 NULL's.

The

full outer join has 3 tuples. 

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function msoCommentShow(anchor_id, com_id)

{

if(msoBrowserCheck())

{

c = document.all(com_id);

a = document.all(anchor_id);

if (null != c && null == c.length && null != a && null == a.length)

{

var cw = c.offsetWidth;

var ch = c.offsetHeight;

var aw = a.offsetWidth;

var ah = a.offsetHeight;

var x = a.offsetLeft;

var y = a.offsetTop;

var el = a;

while (el.tagName != "BODY")

{

el = el.offsetParent;

x = x + el.offsetLeft;

y = y + el.offsetTop;

}

var bw = document.body.clientWidth;

var bh = document.body.clientHeight;

var bsl = document.body.scrollLeft;

var bst = document.body.scrollTop;

if (x + cw + ah / 2 > bw + bsl && x + aw - ah / 2 - cw >= bsl )

{ c.style.left = x + aw - ah / 2 - cw; }

else

{ c.style.left = x + ah / 2; }

if (y + ch + ah / 2 > bh + bst && y + ah / 2 - ch >= bst )

{ c.style.top = y + ah / 2 - ch; }

else

{ c.style.top = y + ah / 2; }

c.style.visibility = "visible";

} } }

function msoCommentHide(com_id)

{

if(msoBrowserCheck())

{

c = document.all(com_id);

if (null != c && null == c.length)

{

c.style.visibility = "hidden";

c.style.left = -1000;

c.style.top = -1000;

} }

}

function msoBrowserCheck()

{

ms = navigator.appVersion.indexOf("MSIE");

vers = navigator.appVersion.substring(ms + 5, ms + 6);

ie4 = (ms > 0) && (parseInt(vers) >= 4);

return ie4;

}

if (msoBrowserCheck())

{

document.styleSheets.dynCom.addRule(".msocomanchor","background: infobackground");

document.styleSheets.dynCom.addRule(".msocomoff","display: none");

document.styleSheets.dynCom.addRule(".msocomtxt","visibility: hidden");

document.styleSheets.dynCom.addRule(".msocomtxt","position: absolute");

document.styleSheets.dynCom.addRule(".msocomtxt","top: -1000");

document.styleSheets.dynCom.addRule(".msocomtxt","left: -1000");

document.styleSheets.dynCom.addRule(".msocomtxt","width: 33%");

document.styleSheets.dynCom.addRule(".msocomtxt","background: infobackground");

document.styleSheets.dynCom.addRule(".msocomtxt","color: infotext");

document.styleSheets.dynCom.addRule(".msocomtxt","border-top: 1pt solid threedlightshadow");

document.styleSheets.dynCom.addRule(".msocomtxt","border-right: 2pt solid threedshadow");

document.styleSheets.dynCom.addRule(".msocomtxt","border-bottom: 2pt solid threedshadow");

document.styleSheets.dynCom.addRule(".msocomtxt","border-left: 1pt solid threedlightshadow");

document.styleSheets.dynCom.addRule(".msocomtxt","padding: 3pt 3pt 3pt 3pt");

document.styleSheets.dynCom.addRule(".msocomtxt","z-index: 100");

}

// -->

processed

SELECT first_name , last_name ,distinct(first_name)

AS Official_mail FROM Staffs;

SELECT first_name , last_name, concat('@usth.edu.vn',

first_name) AS Official_mail FROM Staffs;

SELECT first_name ,

last_name, concat(last_name, '. ', first_name, '@usth.edu.vn ') AS

Official_mail FROM Staffs;

a specific type such as an integer, text, date,

logical, etc.

a coherent set of similar objects that we want

to store data on (e.g. STUDENT, COURSE, CAR)

defined when the database is actually

constructed