Any help would be much appreciated as it will assist me in learning MySQL. FROM tablename WHERE condition Note: A view always shows up-to-date data The database engine recreates the view, every time a user queries it. See Section 13.1.8, ALTER TABLE Statement. CREATE INDEX is mapped to an ALTER TABLE statement to create indexes. CREATE INDEX enables you to add indexes to existing tables. How would I go about creating the desired view from the following tables? CREATE TABLE ClassįOREIGN KEY(ClassId) REFERENCES Class(ClassId)įOREIGN KEY (EmpId) REFERENCES Professor(EmpId) This guideline is especially important for InnoDB tables, where the primary key determines the physical layout of rows in the data file. I tried to create the view with the SQL Query: CREATE SQL SECURITY INVOKER VIEW ClassesView AS SELECT Qualified.ClassId, Teaches.Semester, CONCAT(Professor.FName, Professor.LName) AS Name, Teaches.Section FROM Teaches, Professor, Qualified WHERE Qualified.EmpId = Professor.EmpId, Qualified.ClassId = Teaches.Class īut that didn't work. Identity columns are often used with the PRIMARY KEY. MySQL has no limit on the number of tables. PRIMARY KEY Constraint Open the table structure view ( + + ) Specify the value in the Primary Key box: Add the column name into the Primary Key box to. We can use the optional column constraint IDENTITY to provide a unique, incremental value for that column. An error occurs if the table exists, if there is no default database, or if the database does not exist. MySQL primary key is a single or combination of the field, which is used to identify each record in a table uniquely. By default, tables are created in the default database, using the InnoDB storage engine. You must have the CREATE privilege for the table. I am trying to create a view from the following tables that gives classId, semester, professor's name that taught it, and the number of sections offered that semester. CREATE TABLE creates a table with the given name.
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