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ammarkhan
Front End Web Development Techdegree Student 21,661 PointsWhy use IN, where = make sense?
Just wondering, the proper wording should be
sql "select * from <table> where <col name> = (val1, val2 , val3)" instead of this,
sql "select * from <table> where <col name> IN (val1, val2 , val3)" i mean doesn't that make more sense and easy to remember
2 Answers
Adam Brougher
963 PointsSeems like '"IN" means "included".
SELECT * FROM books WHERE date IN (1999, 2005, 1900);
Select all from books where date is included (here); Select all from books where date is not included (here) ;
Steven Parker
231,184 PointsIt doesn't make sense because IN compares with a list of values, and = only compares with a single value.
Now if you're wondering why SQL wasn't created that way, perhaps it's because:
- SQL has been around a long time (early 1970's)
- the concept of operator overloading was not a common feature of languages then
- it's a mathematical/business language, not a scientific one
ammarkhan
Front End Web Development Techdegree Student 21,661 PointsHow would one choose 2 values using IN op? Like i want to find our if <val1> or <val2> exists in a column using IN?