用jooq选择条件

Question

在SQL中，我可以执行以下类型的查询：

SELECT cost > 1000 AS above_k, name FROM products;

+---------+--------+
| above_k | name   |
+---------+--------+
| true    | Gold   |
| false   | Silver |
+---------+--------+

ctx.select(Tables.PRODUCTS.COST.gt(1000))

因为，没有方法select(Condition Condition)。或者如果我只是想：

SELECT cost*0.9 AS discounted_cost FROM products;

有没有一种方法可以使用Jooq来做到这一点？

Answer 1

sql prettyprint-override">SELECT cost > 1000 AS above_k, name 
FROM products;

ctx.select(field(PRODUCTS.COST.gt(1000)).as("above_k"), PRODUCTS.NAME)
   .from(PRODUCTS)
   .fetch();

请参见DSL.Field（Condition)

SELECT cost*0.9 AS discounted_cost 
FROM products;

ctx.select(PRODUCTS.COST.mul(0.9).as("discounted_cost"))
   .from(PRODUCTS)
   .fetch();

请参阅field.mul(Number)或field.multiply(Number)