// 1) executeUpdate ??” statements that modify the database
// 2) executeQuery ??” SELECT statements (reads)
// *3) execute ??” procedures with multiple SQL
// statements
callStmt.execute();
Everything that one might do interactively using SQL commands can be done programmatically from a
Java program using JDBC.
SUMMARY
Although several types of database exist, almost all database systems in wide use today conform to the
relational database model first described by Codd in 1970. Data are stored in tables where each row is unique,
and each column holds the value of a particular item of data. Rows in each table are identified by a unique key
value, which can be the value of a particular key column, or a combination of values from more than one
column.
Database systems offer advantages by storing data with a minimum amount of redundancy, speeding access
to data, providing security and backup of data, and controlling multiuser access. Databases also offer transaction
management to insure that related modifications to the database either all succeed, or that no change at all
is made. By storing metadata as well as data, databases also allow programs and users to access the
information without concern for the details of physical storage.
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