The main difference in the example above is that the method is called to allow duplicate index keys.
Cost of updating secondary indices Sexci chating mobile number
Therefore, what that means is that an UPDATE of a secondary index column means deleting the old record and inserting a new one.
Although, I did point out some disadvantages, but the fact is that these disadvantages can not be weighted down by the tremendous amount of benefits that comes with clustering in Inno DB.
But, a clustered index can comprise of multiple columns (a composite index), in the same way as a telephone directory is organized both by the first name and the last name.
Inno DB stores indexes as B tree data structures, and same is the case with the clustered index.
When thinking of a clustered index think of a telephone directory, where data is physically arranged by the last name.
Because the clustered index decides the physical storage order of the data in the table, a table can only have a single clustered index.A Secondary Config object is used to configure the secondary database.The Secondary Config class extends the Database Config class, and most steps for configuring a secondary database are the same as for configuring a primary database.Given a city value, we would like to be able to find the Suppliers in that city.Note that more than one Supplier may be in the same city.When lookups by secondary key are performed, the associated record in the primary database is transparently retrieved by its primary key and returned to the caller.