（JDBC）if文と複数の条件を指定したMysqlクエリ

Question

このようなmysql-java文の正しい構文は何ですか？

PreparedStatement st =connection.prepareStatement("SELECT Name, Value, Quantity FROM sales if (type=='Purchase' AND state=='confirmed') OR (type=='Sale' AND state=='not confirmed')) ; 

Answer 1

SQLは次のようになります。clause, and the equality check operator in SQL is = , not `==場合、条件はwhere clause, not anにする必要があります

SELECT Name, Value, Quantity 
FROM sales 
WHERE (type = 'Purchase' AND state = 'confirmed') OR 
     (type = 'Sale' AND state = 'not confirmed'); 

Answer 2

。したがって：

SELECT Name, Value, Quantity 
FROM sales 
WHERe (type = 'Purchase' AND state = 'confirmed') OR 
     (type = 'Sale' AND state = 'not confirmed')