NOT NULL indicates that the column cannot have a NULL value for any record; NULL indicates that NULL is a valid value (even when the column has a foreign key constraint).
NULL is defined as "a missing unknown value," and it is treated differently than other values. Because the result of any arithmetic comparison with NULL is also NULL, such comparisons yield no meaningful results. In MySQL, false is 0 or NULL, and true is anything else.
NOT NULL indicates that the column cannot have a NULL value for any record; NULL indicates that NULL is a valid value (even when the column has a foreign key constraint).
In MySQL, you use the ALTER TABLE MODIFY command to remove a NOT NULL constraint for a column and then restate the column definition, eliminating the NOT NULL attribute.
NULL is defined as "a missing unknown value," and it is treated differently than other values. Because the result of any arithmetic comparison with NULL is also NULL, such comparisons yield no meaningful results. In MySQL, false is 0 or NULL, and true is anything else.
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Karan kadam
5
thank you sir!!!
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savnesh daksh
5
Good
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Sparsh Gaur
4
arey kiske barabar
ARPIT ARORA
5
Error is 11:35:07 SELECT * FROM PRODUCTS group by PROD_CODE LIMIT 0, 1000 Error Code: 1055. Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'learn_vern.PRODUCT
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Swapnil Chilwant
5
Well, a structured course, with amazing teaching techniques by meet shah sir Thank you, LearnVern team.
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Sunil Bhargav
5
good
G
Ganesh Kandu
5
you didn't mentioned about self join
M
mukul kumar
4
please make a assignment solution video, explanation is very good
S
saurabh kushwah
5
Thank you LearnVern to teach us the best courses at no cost these courses are very amazing keep going and keep teaching as same as you doing. Please add DSA course also.
M
Manabendra Nath
4
Bahoot ascha samjhate hain lekin, thora sa slow samjhata hain jo thora booring lagte hain,(Just my opinion). Thank you.
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