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Data Analysis

Ambiguous column name error.

hi, I am trying the following query but I get ambiguous column name error. Please advise how can I fix it?

SELECT * FROM SUBJECTS JOIN SUBJECTS ON SUBJECTS.NAME = CLASSES.SUBJECT_ID;

1 Answer

Hello, bummer you had to wait so long for a response. Better late than never.

An ambiguous column name error usually means that you have a column name that appears in two tables so you need to clarify or that your column name is already defined within sql.

In your code you appear to be joining a table Subjects to itself (FROM SUBJECTS JOIN SUBJECTS ). I think you meant to join subjects to classes. Also, the column you join the tables on have to have the same values. Subject_ID in the Classes table is a number. The Name column in the Subject table is text. Yo need to find the column that classes and subject table have in common and join on that.

GOOD LUCK!