开发者

SELECT two fields from single column based on value in second column

I'm a database newb, so please forgive me if this has been covered a million times before, I'm not finding a solution for what I'm trying to do.

I have a table - we'll call 'product_attributes', where a number of specific attributes are stored for all the products. In this table, 'attribute_id' tells me what type of information is stored in the row, 'store_id' tells me which website the information is displayed on, 'entity_id' tells me what product the information is about and 'value' is information about the product. Format is:

value_id    entity_type_id    attribute_id    store_id    entity_id    value
1221        4                 57              0           306          Detailed Description of Product
1222        4                 58              0           306          Quick Overview of Product
1223        4                 68              0           306          metakeywords
1224        4                 89              0           306          metadescription
1225        4                 93              0           306          Other Stuff
1226        4                 57              0           307          Detailed Des开发者_开发技巧cription of Product
1227        4                 58              0           307          Quick Overview of Product
1228        4                 68              0           307          metakeywords
1229        4                 89              0           307          metadescription
1230        4                 93              0           307          Other Stuff

I need to run a query to pull all items from the column 'value' with 'attribute_id=57' into a column called 'Long Description' and all items from the same column with 'attribute_id=58' into another column called 'Short Description'. I can get the values individually easy enough with:

SELECT product_attributes.value FROM product_attributes WHERE attribute_id=57

or

SELECT product_attributes.value FROM product_attributes WHERE attribute_id=58

But I need a separate column for each like this:

Long Description                      Short Description
Detailed Info of 'entity_id 306'      Overview of 'entity_id 306'
Detailed Info of 'entity_id 307'      Overview of 'entity_id 307'


SELECT pr1.value as LongDescription, pr2.value as ShortDescription 
FROM product_attributes pr1 
JOIN product_attributes as pr2 
WHERE pr1.attribute_id=57 AND pr2.attribute_id=58


select a.value as 'long desc', b.value as 'short desc'
from
(SELECT entity_id, product_attributes.value FROM product_attributes WHERE attribute_id=57 ) a,
(SELECT entity_id, product_attributes.value FROM product_attributes WHERE attribute_id=58 ) b
where a.entity_id = b.entity_id


select (SELECT a.value FROM product_attributes as a where a.attribute_id=57) as LongDescription,(SELECT b.value FROM product_attributes as b where b.attribute_id=58) as ShortDescription from product_attributes

This may help U..

0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜