BigQuery SQL - 我怎么知道最小值、最大值和平均值？

Question

Here's the output:

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Hello, i would like to know if it's possible to know the min, max and average "year_birth" other than looking for it manually?

Here's my following code (it might be super bad, it's because i'm beginning with SQL)

 WITH clean_profils as( SELECT *, REPLACE(Marital_Status,"Alone","Single") AS Clean_Marital_Status FROM `neoma-bdd.data.profils` WHERE Year_Birth > 1940 AND Marital_Status <> "YOLO" and Marital_Status <> "Absurd" AND Income IS NOT null ) SELECT clean_profils.id, Year_Birth, Income, Kidhome, Teenhome, Dt_Customer, Clean_Marital_Status, MntWines + MntFruits + MntMeatProducts + MntFishProducts + MntSweetProducts + MntGoldProds AS ALL_PURCHASES, FROM `neoma-bdd.data.purchases` INNER JOIN clean_profils ON `neoma-bdd.data.purchases`.id = clean_profils.id ORDER by ALL_PURCHASES LIMIT 560

Bonus question, i'm doing a segmentation as follow : 

Quartile 1 : 1 rows to 559,75 rows
Quartile 2 : 559,75 rows to 1119 rows
Médiane : 1119,5 
Quartile 3 : 1120 rows to 1679,75 rows
Quartile 4 : 1679,75 rows to 2240 rows

how can i select only the 560 to 1119 rows based on "All_Purchases"

i tried self joining but it didn't help me at all :/ 

Answer 1

It seems a simple question

SELECT AVG(Year_Birth) as Average

should provide the mean

 SELECT APPROX_QUANTILES(Year_Birth, 2) AS approx_quantiles

or if there are nulls in your data

SELECT FORMAT("%T", APPROX_QUANTILES(Year_Birth, 2 RESPECT NULLS)) AS approx_quantiles

should provide you with a min, median and max

SELECT
  APPROX_TOP_COUNT(Year_Birth,1) AS mode

should provide you with the mode