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Question : How to get a one-to-many result set in mysql
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Hi,
Let's say I have a database with 2 tables, foodtypes and foodnames (show below). Foodtypes has 3 different types of food and foodnames has examples of things that belong in that type. I use these tables to post on a webpage. If you select the type of food in a form, then you get back the different foods in the type that you selected.
foodtypes
-----------------
|ID | Name |
-----------------
|1 |Meat |
|2 |Fruit |
|3 |Vegetable |
-----------------
foodnames
-----------------------------
|ID | Type | Name |
-----------------------------
|1 |1 |Pork |
|2 |1 |Beef |
|3 |2 |Apple |
|4 |3 |Broccoli |
|5 |2 |Pear |
|6 |2 |Strawberry |
|7 |3 |Peas |
|8 |1 |Chicken |
|9 |1 |Goat |
|10 |3 |Celery |
-----------------------------
If I execute the query:
Select a.Name, b.Name, b.ID from foodtypes a, foodnames b where a.ID=b.Type and a.ID in (2,3);
the expected outcome would be:
-------------------------------
| a.Name |b.Name |b.ID |
-------------------------------
|Fruit |Apple |3 |
|Fruit |Pear |5 |
|Fruit |Strawberry |6 |
|Vegetable |Broccoli |4 |
|Vegetable |Celery |10 |
|Vegetable |Peas |7 |
-------------------------------
Is there a way to design the query so that I dont get repeated values of a.Name, the type of food. I want to be able to refine it so that the result would be similar except Fruit and Vegetable only appear once. For example:
----------------------------------
| a.Name |b.Name |b.ID |
-----------------------------------
|Fruit |Apple |3 |
| |Pear |5 |
| |Strawberry |6 |
|Vegetable |Broccoli |4 |
| |Celery |10 |
| |Peas |7 |
-----------------------------------
Is this even possible using mysql? Would I need to use php? Is there a way I can call it using php and then manipulate afterwards so that it prints the way I want it to? Does what I'm asking for make sense?
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Answer : How to get a one-to-many result set in mysql
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You could ask another question to get a quick(er) response (?) :)
Try this
$dupDetect = "";
$dup2Detect = "";
while($row = mysql_fetch_row($query)) {
echo "<tr class='tab_bg_1'>";
$colindex = 1;
$col2index = 1;
foreach ($row as $str) {
if ($colindex==1) { // change this to the column index desired
if ($str == $dupDetect ) {
$str=''; // blank if it is the same as previous
}
else {
$dupDetect = $str; // store it to compare against next
$dup2Detect = ""; // reset dup2 at the same time
}
} else if ($colindex==2) {
if ($str == $dup2Detect ) {
$str=''; // blank if it is the same as previous
}
else {
$dup2Detect = $str; // store it to compare against next
}
}
echo "<td>".$str."</td>";
$colindex++;
}
echo "</tr>";
}
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