The Short details of this question is that if i have a database let’s say an fruit and i have define a the table as fruit_details_tbl . So, inside this table i have a column for the different criteria or aspects you can say like a color , shape, taste,etc. So, Now i have made a shape as NULL and other fields as required then how much null value i can specify for that column.
Create table fruit_details_tbl(name varchar(20) NOT NULL,shape varchar(20) NULL ,color varchar(20) NOT NULL,taste varchar(20) NOT NULL);
In SQL, the NULL data type represents the absence of a value. When defining a column as NULL, it means that the column can contain NULL values. The number of NULL values that can be specified for a NULL data type column is unlimited. This means that you can have any number of NULL values in a column defined as NULL.
In your example, the “shape” column in the “fruit_details_tbl” table is defined as NULL. This means that you can have any number of NULL values in the “shape” column. Other columns like “name”, “color”, and “taste” are defined as NOT NULL, which means they cannot contain NULL values.
To insert NULL values into the “shape” column, you can use the INSERT statement and specify NULL as the value for the “shape” column:
INSERT INTO fruit_details_tbl (name, shape, color, taste)VALUES ('Apple', NULL, 'Red', 'Sweet');
INSERT INTO fruit_details_tbl (name, shape, color, taste)
VALUES ('Apple', NULL, 'Red', 'Sweet');
You can insert multiple rows with NULL values in the “shape” column if needed.