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Databases

jobbol
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jobbol
Full Stack JavaScript Techdegree Student 16,610 Points
Posted by jobbol
.a{fill-rule:evenodd;}techdegree
jobbol
Full Stack JavaScript Techdegree Student 16,610 Points

How to select and join two tables but replace IDs with matching values?

I have two tables: task and area_name. I need a select which gets everything from the task table, but replaces the ID value with the matching name from the name table.

task

area_id  |  description   |   ...
----------------------------------
1        |  Mow lawn      |
2        |  Clean dishes  |
4        |  Fold clothes  |

area_name

area_id |  name
----------------------
1       |  Yard
2       |  Kitchen
3       |  Living room
4       |  Laundry room

wanted result

area          |  description   |   ...
----------------------------------------
Yard          |  Mow lawn      |
Kitchen       |  Clean dishes  |
Laundry room  |  Fold clothes  |

My code looks like this,

SELECT * FROM `task` as t1
LEFT JOIN `area_name` as t2 ON t1.area_id = t2.area_id;

But this returns

area_id  |  description   |   ...  | area_id  | area          |
-------------------------------------------------------------
1        |  Mow lawn      |        | 1        | Yard          |
2        |  Clean dishes  |        | 2        | Kitchen       |
4        |  Fold clothes  |        | 4        | Laundry room  |

Obviously there's an easy solution by picking the columns that select returns,

SELECT name AS area, description FROM `task` as t1
LEFT JOIN `area_name` as t2 ON t1.area_id = t2.area_id;

However I'm not looking to list each column in the query, as my task table in reality is 12 columns or so long, and I don't want to maintain this as I change the schema. I'm looking for a shortcut if it's possible.

1 Answer

ivana kantnerova
ivana kantnerova
15,932 Points
ivana kantnerova
ivana kantnerova
15,932 Points

i think should be like this ..

select t2.name as area, t1.description from task as t1 inner join area_name as t2 on t1.area_id = t2.area_id;