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Use sql command to modify a field in the data table to be non-null (not null)_PHP tutorial
Use sql command to modify a field in the data table to be non-null (not null)_PHP tutorial
ALTER TABLE table1 ALTER COLUMN [name] varchar(60) NULL;
table1 table name
Why is [] added to the name field name, because name is SQL keyword conflicts will cause errors, just in case.
If an index has been created for the name field, if it needs to be modified, the index must be deleted first to proceed correctly.
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