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An existing MySQL table has a DateTime field which is not null and having a Default Value set as '0001-00-00 00:00:00'. Is it possible to Alter this table to remove the default value for the DateTime field ?
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To change a default value, use ALTER col_name SET DEFAULT : ALTER TABLE mytbl ALTER j SET DEFAULT 1000; Default values must be constants. For example, you cannot set the default for a date-valued column to NOW( ) , although that would be very useful.
To enforce NOT NULL for a column in MySQL, you use the ALTER TABLE .... MODIFY command and restate the column definition, adding the NOT NULL attribute.
Set a default valueRight-click the control that you want to change, and then click Properties or press F4. Click the All tab in the property sheet, locate the Default Value property, and then enter your default value.
Syntax: ALTER TABLE <table_name> ALTER COLUMN <column_name> DROP DEFAULT; Example: Lets say we want to drop the constraint from STUDENTS table, which we have created in the above sections.
Yes, you can drop the default using an ALTER TABLE statement like this:
alter table your_table alter column your_column drop default; To drop the default from multiple datetime columns in a table:
ALTER TABLE your_table ALTER COLUMN columnname1 DROP DEFAULT, ALTER COLUMN columnname2 DROP DEFAULT, ALTER COLUMN columnname3 DROP DEFAULT, .... If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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