Using an IF Statement in MySQL

Question

I have the below SQL statement. What I would like to do is include an IF statement to cover the possibility of one of the columns returning a 0 or blank result, there are no 0 ID's. In this case, I'm trying to cover the possibility of the magez_cfv_nations result possibly returning a zero or blank result.

SELECT c.clan_name, n.nation_name, 
    CONCAT(r.rarity_shorthand, " - ", r.rarity_name) AS rarity_text, 
    t.trigger_name, s.skill_name
 FROM `magez_cfv_cards` AS cards
 JOIN `magez_cfv_clans` c ON cards.clan_id = c.clan_id
 JOIN `magez_cfv_nations` n ON cards.nation_id = n.nation_id
 JOIN `magez_cfv_rarity` r ON cards.rarity_id = r.rarity_id
 JOIN `magez_cfv_trigger` t ON cards.trigger_id = t.trigger_id
 JOIN `magez_cfv_skills` s ON cards.skill_id = s.skill_id

Answer 1

You need a LEFT JOIN

The LEFT JOIN keyword returns all rows from the left table (table_name1), even if there are no matches in the right table

Try this

SELECT c.clan_name, n.nation_name, 
    CONCAT(r.rarity_shorthand, " - ", r.rarity_name) AS rarity_text, 
    t.trigger_name, s.skill_name
 FROM `magez_cfv_cards` AS cards
 JOIN `magez_cfv_clans` c ON cards.clan_id = c.clan_id
 LEFT JOIN `magez_cfv_nations` n ON cards.nation_id = n.nation_id
 JOIN `magez_cfv_rarity` r ON cards.rarity_id = r.rarity_id
 JOIN `magez_cfv_trigger` t ON cards.trigger_id = t.trigger_id
 JOIN `magez_cfv_skills` s ON cards.skill_id = s.skill_id

Answer 2

the function you should use is IIF() and its syntax is

IIF([condition],[if true],[if false])