documentclass[border=0.25in]{standalone}

usepackage{tikz}
usetikzlibrary{shapes.multipart}
usetikzlibrary{matrix}
usetikzlibrary{positioning}
usetikzlibrary{shadows}
usetikzlibrary{calc}

makeatletter
pgfarrowsdeclare{crow's foot}{crow's foot}
{
  pgfarrowsleftextend{+-.5pgflinewidth}%
  pgfarrowsrightextend{+.5pgflinewidth}%
}
{
  pgfutil@tempdima=0.5pt%
  advancepgfutil@tempdima by.25pgflinewidth%
  pgfsetdash{}{+0pt}%
  pgfsetmiterjoin%
  pgfpathmoveto{pgfqpoint{0pt}{-6pgfutil@tempdima}}%
  pgfpathlineto{pgfqpoint{-6pgfutil@tempdima}{0pt}}%
  pgfpathlineto{pgfqpoint{0pt}{6pgfutil@tempdima}}%
  pgfusepathqstroke%
}


tikzset{
    entity/.code={
        tikzset{
            label=above:#1,
            name=#1,
            inner sep=0pt,
            every entity/.try,
            fill=white,
            general shadow={
                shadow xshift=0.0625in,
                shadow yshift=-0.0625in,
                opacity=0.5,
                fill=black!50
            }
        }%
        defentityname{#1}%
    },
    entity anchor/.style={matrix anchor=#1.center},
    every entity/.style={
            draw,
    },
    every property/.style={
        inner xsep=0.25cm, inner ysep=0.125cm, anchor=west, text width=1in
    },
    zig zag to/.style={
        to path={(tikztostart) -| ($(tikztostart)!#1!(tikztotarget)$) |- (tikztotarget)}
    },
    zig zag to/.default=0.5,
    one to many/.style={
        -crow's foot, zig zag to
    },
    many to one/.style={
        crow's foot-, zig zag to
    },
    many to many/.style={
        crow's foot-crow's foot, zig zag to
    }
}
defproperty#1{node[name=entityname-#1, every property/.try]{#1};}
defproperties{begingroupcatcode`_=11relaxprocessproperties}
defprocessproperties#1{endgroup%
    defpropertycode{}%
    foreach p in {#1}{%
        expandafterexpandafterexpandaftergdefexpandafterexpandafterexpandafterpropertycode%
            expandafterexpandafterexpandafter{expandafterpropertycodeexpandafterpropertyexpandafter{p}\}%
    }%
    propertycode%
}

begin{document}

begin{tikzpicture}[every node/.style={font=ttfamily}, node distance=1.25in]
matrix [entity=Class] {
    properties{
        classkey,
        class_type,
        class_desc
    }
};

matrix [entity=Product, right=of Class-classkey, entity anchor=Product-classkey]  {
    properties{
        classkey,
        prodkey,
        prod_name,
        pkg_type
    }
};

matrix  [entity=Sales, right=of Product-classkey, entity anchor=Sales-classkey]  {
    properties{
        perkey,
        classkey,
        prodkey,
        prod_name,
        storekey,
        promokey,
        quantity,
        dollars
    }
};

matrix  [entity=Period, right=of Sales-perkey, entity anchor=Period-perkey]  {
    properties{
        perkey,
        date,
        day,
        week,
        month,
        qtr,
        year
    }
};

matrix  [entity=Promotion, below=of Period, entity anchor=Promotion-promokey]  {
    properties{
        promokey,
        promo_type,
        promo_desc,
        value,
        start_date,
        end_date
    }
};

matrix  [entity=Store, below=of Product, entity anchor=Store-storekey]  {
    properties{
        storekey,
        mktkey,
        store_type,
        store_name,
        street,
        city,
        state,
        zip
    }
};

matrix  [entity=Market, left=of Store-mktkey, entity anchor=Market-mktkey]  {
    properties{
        mktkey,
        hq_city,
        hq_state,
        district,
        region
    }
};

draw [one to many] (Class-classkey)   to (Product-classkey);
draw [one to many] (Product-classkey) to (Sales-classkey);
draw [one to many] (Product-prodkey)  to (Sales-prodkey);
draw [many to one] (Sales-perkey)     to (Period-perkey);
draw [one to many] (Market-mktkey)    to (Store-mktkey);
draw [many to one] (Sales-storekey)   to (Store-storekey);
draw [many to one] (Sales-promokey)   to (Promotion-promokey);

end{tikzpicture}

end{document}

pgfdeclarearrow{
  name = ErdMany,
  parameters = {
    thepgfarrowlength
  },
  setup code = {
    % End values
    pgfarrowssettipend{pgfarrowlength}
    pgfarrowssetbackend{0pt}
    pgfarrowssetlineend{pgfarrowlength}
    pgfarrowssetvisualbackend{pgfarrowlength}
    % Convex hull
    pgfarrowshullpoint{0pt}{0pt}
    pgfarrowshullpoint{pgfarrowlength}{pgfarrowlength}
    pgfarrowshullpoint{pgfarrowlength}{-pgfarrowlength}
    % Save
    pgfarrowssavethepgfarrowlength
  },
  drawing code = {
    pgfpathmoveto{pgfqpoint{pgfarrowlength}{0.5pgfarrowlength}}
    pgfpathlineto{pgfqpoint{0pt}{0pt}}
    pgfpathlineto{pgfqpoint{pgfarrowlength}{-0.5pgfarrowlength}}
    pgfusepathqstroke
  },
  defaults = { length = 10pt }
}