Mysql Simple Query question
I wrote out this Mysql query, but return a lot of blank fields for the customers_telephone table
since it was never a required field. I would like to return some dummy data on my
query (without inserting it into the database) if the field is NULL. I know MySQL
uses if clauses but I think it's only for creating databases or ... ?
here's my stamp
SELECT orders.orders_id AS recipient_id, delivery_company, delivery_street_address, delivery_city, delivery_postcode, delivery_state, delivery_country, customers_telephone
FROM orders, orders_products
WHERE orders.orders_id = orders_products.orders_id
AND products_id = 416
ORDER BY `orders`.`orders_id` DESC
UPDATE
I tried doing this, but it still is not working, maybe I did it in the wrong place?
SELECT orders.orders_id AS recipient_id, delivery_company, delivery_street_address, delivery_city, delivery_postcode, delivery_state, delivery_country, IFNULL(customers_telephone, 'no number') AS customers_number
FROM orders, orders_products
WHERE orders.orders_id = orders_products.orders_id
AND products_id = 416
ORDER BY `orders`.`orders_id` DESC
Returns
recipient_id delivery_company delivery_street_address deliv开发者_JS百科ery_city delivery_postcode delivery_state delivery_country number
191743 This Chick Bakes 31-31 48th Ave #B Long Island City 11101 NY United States 917.848.6437
191724 44 Miraflores Ave (studio) San Rafael 94901 CA United States
191723 397 South River Street Wilkes-Barre 18702 PA United States
Use the IFNULL function to provide a value if the field is NULL:
IFNULL(customers_telephone, 'dummydata') AS customers_telephone
IFNULL is a non-standard MySQL extension. The standard way is to use the COALESCE function for this purpose. COALESCE is also supported by MySQL, but it is slightly slower than IFNULL, though it probably won't matter here.
One way
SELECT COALESCE(customers_telephone, 'no number') FROM ...
加载中,请稍侯......
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