How to compare two columns from two dataframes and return values from a third column?

Question

On first dataframe, I have some product SKU codes and their respectives unique IDs. In the other one I have the SKUs of several products, including some of the first dataframe. I want to get the unique product ids from df1 and assign them to df2, also completing the SKU numbers that don't match:

Example:

df1:                                df2:

sku     | unique_id                 sku     |
------- | ---------                 ------- | 
4fd5.88 | 1                         4fd5.88 | 
d545.99 | 2                         d545.99 | 
hy12.33 | 3                         h999.21 |

Desired output:

df1:                                df2:

sku     | unique_id                 sku     | unique_id
------- | ---------                 ------- | ---------
4fd5.88 | 1                         4fd5.88 | 1
d545.99 | 2                         h999.21 | 3
hy12.33 | 3                         d545.99 | 2

this h999.21 don't exists in df, how its mapped to 3? – Naveed Oct 17 '22 at 17:03 — Naveed, Oct 17 '22 at 17:03

score 1 · Answer 1 · answered Oct 17 '22 at 17:03

1

df2['unique_id']=df2['sku'].map(df.set_index(['sku'])['unique_id'])
df2

sku     unique_id
0   4fd5.88     1.0
1   d545.99     2.0
2   h999.21     NaN

answered Oct 17 '22 at 17:03

Naveed

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How to compare two columns from two dataframes and return values from a third column?

1 Answers1