Dec 15, 2013 · My question is I could not understand the meaning of "ENABLE" in this statement. What would be the difference if we just define as "NAME" ...

Oct 11, 2010 · According to the SQL Specification, a primary key can not contain NULL. This means that decorating a column with either "NOT NULL PRIMARY KEY" ...

May 5, 2012 · A PRIMARY KEY is a unique index where all key columns must be defined as NOT NULL . If they are not explicitly declared as NOT NULL , MySQL ...

Dec 4, 2021 · The error is obvious: column room_charges in table room_details is not primary key or unique. It probably really isn't unique; the primary key ...

Dec 2, 2012 · In most DBMS, since its a primary key (and the definition of is that it must be unique within the table) then it most certainly cannot be null.

Apr 26, 2017 · First, the error was that can not infer a primary key from the colums, so I add a pk to the view. Now says that primary key is not valid because ...

Jun 21, 2018 · In the database there is a table foo , which has no primary key, just 2 columns, id and name . In Java there is an @Entity Foo ...

May 29, 2009 · My question is in regards to the use of primary keys as functional parts of a table (and not assigning "ID" numbers to every table just because) ...