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POWhat can I expect from this query using NOT IN?
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copied!<p>What is the result if you try to run the following query? Assume for this query that all books have a value for publ_id and no publ_id is 90 </p> <pre><code>Select * From a_bkinfo.books Where publ_id not in (90, null); </code></pre> <p>I ran the query and received no rows, but I thought it this would return rows where the publ_id is not 90. I am confused. What am I not seeing? </p> <pre><code>Table: -- create publishers create table a_bkinfo.publishers ( publ_id integer not null , publ_name varchar(25) not null , constraint bk_publishers_pk primary key(publ_id) , constraint publ_id_range check (publ_id >1000) )engine = INNODB; Inserts: -- publishers Insert into a_bkinfo.publishers values (9000, 'Microsoft Press') ; Insert into a_bkinfo.publishers values (9456, 'New Directions') ; Insert into a_bkinfo.publishers values (9102, 'Alfred A. Knopf') ; Insert into a_bkinfo.publishers values (9325, 'Addison Wesley') ; Insert into a_bkinfo.publishers values (9745, 'Morgan Kaufmann') ; Insert into a_bkinfo.publishers values (9521, 'Benjamin/Cummings') ; Insert into a_bkinfo.publishers values (9822, 'O''Reilly') ; Insert into a_bkinfo.publishers values (9030, 'McGraw Hill') ; Insert into a_bkinfo.publishers values (9444, 'APress') ; Insert into a_bkinfo.publishers values (9528, 'Manning'); Insert into a_bkinfo.publishers values (9020, 'Princeton Univer Press') ; Insert into a_bkinfo.publishers values (9021, 'Yale University Press') ; Insert into a_bkinfo.publishers values (9022, 'Havard University Press') ; Insert into a_bkinfo.publishers values (9507, 'J.Q. Vanderbildt'); Insert into a_bkinfo.publishers values (9664, 'WROX') ; Insert into a_bkinfo.publishers values (9825, 'MySQL Press') ; Insert into a_bkinfo.publishers values (9623, 'Prentice Hall') ; Insert into a_bkinfo.publishers values (9725, 'Springer') ; Insert into a_bkinfo.publishers values (9561, 'Houghton Mifflin'); Insert into a_bkinfo.publishers values (9902, 'W.W. Norton ') ; Insert into a_bkinfo.publishers values (9023, 'Holt Paperbacks') ; Insert into a_bkinfo.publishers values (9024, 'Univ of California Press') ; Insert into a_bkinfo.publishers values (9776, 'Simon and Schuster') ; </code></pre>

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