Create Table SQL Statement
What is the syntax of CREATE TABLE in Oracle? Since the syntax of CREATE TABLE statement can be very flexible and complicated, so using text-based… Read More »Create Table SQL Statement
NOT NULL
Oracle ALTER TABLE ADD Column By Examples
ALTER TABLE ADD COLUMN In this post, I'll show you some practical examples of adding a column to table from the simplest to the complicated.… Read More »Oracle ALTER TABLE ADD Column By Examples
How to Resolve ORA-01440: column to be modified must be empty to decrease precision or scale
ORA-01440 ORA-01440 means that you can't decrease the number precision of the column values directly by modifying the definition of the column. Let's see a… Read More »How to Resolve ORA-01440: column to be modified must be empty to decrease precision or scale
How to Modify VARCHAR2 to CLOB of a Column
Data Type Conversion There're several major data types built in Oracle. Character Numeric Datetime LONG RAW LOB (Large Object) In each major data types, minor… Read More »How to Modify VARCHAR2 to CLOB of a Column
How to Resolve ORA-01442: column to be modified to NOT NULL is already NOT NULL
ORA-01442 ORA-01442 means that the target column of table is already NOT NULL, so you don't have to add NOT NULL on the column. I… Read More »How to Resolve ORA-01442: column to be modified to NOT NULL is already NOT NULL
How to Resolve ORA-01400: cannot insert NULL into
ORA-01400 ORA-01400 means that there's a column which was found as NOT NULL is not listed in the INSERT statement, you have to provide a… Read More »How to Resolve ORA-01400: cannot insert NULL into
How Oracle Disable NOT NULL Constraint
After you add a NOT NULL constraint to a column, you might want it stop temporarily. In such moment, you should consider to disable NOT… Read More »How Oracle Disable NOT NULL Constraint
How Oracle Add NOT NULL Constraint
Add NOT NULL Constraint As I mentioned in resolving ORA-00904 for adding a constraint, NOT NULL is a constraint, but it's more like an attribute… Read More »How Oracle Add NOT NULL Constraint
How Oracle Remove NOT NULL Constraint
Before we talk about how to remove NOT NULL constraint, I assume that you have already know how to add a NOT NULL constraint to… Read More »How Oracle Remove NOT NULL Constraint
How to Resolve ORA-00904 Invalid Identifier
ORA-00904 ORA-00904 means that you used an invalid identifier to be a column name, which is most likely unmatched in name or incorrect syntax. Since… Read More »How to Resolve ORA-00904 Invalid Identifier