如何将sql中的pivot表？

Question

I need to pivot a table, but I am stuck because of reapeated Action values. Goal: extract values from the Action column and use them as the headers for new columns. Then, fill the new table with values from the Val column. In this instance, there is only one group, so you can utilize a window function to capture all groups with ID column. All SN are unique, but other actions can be repeated for the same SN

I have a table:

Val	Action	ID
SN1844Q	SN	94a52150-a24f-11ed
2000	Check_X	94a52150-a24f-11ed
1	Pass	94a52150-a24f-11ed
2022-01-12 23:51:31	DateTime	94a52150-a24f-11ed
up	Position	94a52150-a24f-11ed
back	Position	94a52150-a24f-11ed
890	Check_X	94a52150-a24f-11ed
SN1845Q	SN	28497a86-8e8e-44da
...	...	...

I want to see:

SN	Check_X	Pass	DateTime	Position
SN1844Q	2000	1	2022-01-12 23:51:31	up
SN1844Q	890	1	2022-01-12 23:51:31	back
...	...	...	...	...

Answer 1

You have to use SQL pivot with a dynamic query click here .

Answer 2

SELECT SN,
       MAX(CASE WHEN Action = 'Action 1' THEN Val END) AS "Action 1",
       MAX(CASE WHEN Action = 'Action 2' THEN Val END) AS "Action 2",
       MAX(CASE WHEN Action = 'Action 3' THEN Val END) AS "Action 3"
FROM original_table
GROUP BY SN

In this query, the MAX function is used in the CASE statement to aggregate the values from the Val column, while the GROUP BY clause is used to group the results by the SN column. The CASE statement is used to match the values in the Action column and return the corresponding values from the Val column. The result of the query will be a new table with columns for each unique value in the Action column, with the values from the Val column filling in the appropriate cells