I got '61678125784' using 1997-01-01 without the quotation mark whereas the answer shows 31909143195 from '1997-01-01'. Why is it so? Please help. Thanks.

Hi Angela!Thanks for reaching out. You can use quotes for both numbers and strings. But usually quotes are for strings. The numbers can be without quotes and in this way there is a better readability. On the other side, dates should be with quotes! If you skip the quotes, the result set will be different and incorrect. Let me show you an example: If you skip the quotes from your query and you have: ...BETWEEN 2000-01-01 AND 1995-05-04...it will be the same as: ...BETWEEN 1986 AND 1998...(1995-05-04=1995-5-4=1986 and 2000-01-01=2000-1-1=1998) which is very different from: ...BETWEEN '2000-01-01' AND '1995-05-04'...The first example has a period of 12 years and the second one with only 5 years. Thus, the result set will be different. So, you should use quotes for dates. Hope this helps.Best,Tsvetelin

Follow this topic

Angela Zhang

Last answered:

15 Mar 2023

Posted on:

15 Mar 2023

exercise question

in SQL / SUM()

1 answers ( 0 marked as helpful)

Tsvetelin Tsonkov

Instructor

Posted on:

15 Mar 2023

exercise question

Submit an answer

related questions