逻辑函数

Power BI 中级 DAX

Carl Rosseel

Curriculum Manager

逻辑函数概览

逻辑函数对表达式求值，返回有关表达式中值或集合的信息。

最常用的逻辑函数：

IF()
AND(), OR(), NOT()
SWITCH()

IF() 是最常用的逻辑函数之一

结构：

IF(<logical_test>, <value_if_true>, <value_if_false>)

示例：

Performance = IF([Total Sales] >= 50 000, "Target Reached", "Target Not Reached")

IF() 是最常用的逻辑函数之一

结构：

IF(<logical_test>, <value_if_true>[, <value_if_false>])

示例：

Performance = IF([Total Sales] >= 50 000, "Target Reached", "Target Not Reached")

Name	Total Sales
Jenny	48,431
Jane	76,528
Dwayne	24,167
Thomas	52,125

IF() 是最常用的逻辑函数之一

结构：

IF(<logical_test>, <value_if_true>[, <value_if_false>])

示例：

Performance = IF([Total_Sales] >= 50 000, "Target Reached", "Target Not Reached")

Name	Total Sales	Performance
Jenny	48,431	Target not Reached
Jane	76,528	Target Reached
Dwayne	24,167	Target Not Reached
Thomas	52,125	Target Reached

AND(), OR() 与 NOT() 运算符

三者均返回 TRUE 或 FALSE。

AND(<logical1>,<logical2>)
- 若两条件均为 TRUE，则返回 TRUE
- 示例：AND(5 < 4, 5 < 6) = AND(FALSE, TRUE) = FALSE
OR(<logical1>,<logical2>)
- 若至少一条件为 TRUE，则返回 TRUE
- 示例：OR(5 < 4, 5 < 6) = OR(FALSE, TRUE) = TRUE
NOT(<logical>)
- 将 TRUE 与 FALSE 互换
- 示例：NOT(OR(5 < 4, 5 < 6)) = NOT(TRUE) = FALSE

AND(), OR() 与 NOT() 运算符

AND 可用 && 替代

AND(5 < 4, 5 < 6) = 5 < 4 && 5 < 6

OR 可用 || 替代

OR(5 < 4, 5 < 6) = 5 < 4 || 5 < 6

SWITCH() 的威力

将表达式与一组取值比较，并返回多个结果表达式之一。

SWITCH(<expression>, <value>, <result>[, <value>, <result>] ... [, <else>])

通常优于嵌套的 IF()

Performance = SWITCH(TRUE, 
[Total_Sales] < 25 000, "Poor",
[Total_Sales] < 50 000, "Below expectations",
[Total_Sales] < 75 000, "Above expectations",
"Exceptional")

SWITCH() 的威力

Performance = SWITCH(TRUE, 
[Total_Sales] < 25 000, "Poor",
[Total_Sales] < 50 000, "Below expectations",
[Total_Sales] < 75 000, "Above expectations",
 "Exceptional")

Name	Total Sales
Jenny	48,431
Jane	76,528
Dwayne	24,167
Thomas	52,125

SWITCH() 的威力

Performance = SWITCH(TRUE, 
[Total_Sales] < 25 000, "Poor",
[Total_Sales] < 50 000, "Below expectations",
[Total_Sales] < 75 000, "Above expectations",
 "Exceptional")

Name	Total Sales	Performance
Jenny	48,431	Below Expectations
Jane	76,528	Exceptional
Dwayne	24,167	Poor
Thomas	52,125	Above expectations

SWITCH() 的威力

DISCOUNT = SWITCH([Clothing Type], 
               "Shoes", 0.15,   
               "Pants", 0.20,
               "Belts", 0.30, 
               "T-shirt", 0.25)

Clothing Type
Shoes
Pants
Belt
T-shirt

SWITCH() 的威力

DISCOUNT = SWITCH([Clothing Type], 
               "Shoes", 0.15,   
               "Pants", 0.20,
               "Belts", 0.30, 
               "T-shirt", 0.25)

Clothing Type	Discount
Shoes	15%
Pants	20%
Belt	30%
T-shirt	25%

Let's switch up!

Power BI 中级 DAX