dbAddPrimaryKey: Adds a Primary Key to an existing table

In schardtbc/DBIExt: Extentsion for DBI; new Generics

Description

'dbCreateTable' does not directly support adding primary or secondary indexes to the table being created. Properly chosen indexing of tables increases query performance.

Usage

dbAddPrimaryKey(con, name, primary_key, ...)

Arguments

con	a DBConnection oject
name	a character string specifying the name of an existing DBMS table
primary_key	a character vector of column names which will form the primary key To specify a composite Primary Key for the 'symbol' and 'date' columns use primary_key = c("symbol","date" ) For a table with a Primary Key defined, each records must have a unqiue primary key. Attempts to 'INSERT' records with a duplicate Primary Key to an existing record in the DB will cause an ERROR

Details

The default 'dbAddPrimaryKey()' method performs checks that the targeted table exists and that the columns specified for the primary-key exist in the target table. the method throws an error if either condition is FALSE

The sql generation uses the function 'sqlAlterTableWithPrimaryKey()' another S4 generic defined in this package. Default sql generation is appropriate for MariaDB and MySQL.

See Also

Other DBIConnection generics: dbAddIndex, dbDeleteAllRecords, dbDropTable, dbReplaceInTable, dbUpdateTable

schardtbc/DBIExt documentation built on June 7, 2019, 2:39 p.m.