- Facts:
- The java.sql package
has many data structures
used to
process data
received from the SQL server
- The
Statement
object
in the java.sql package is used to:
- Store an
SQL statement (= query)
(by sending the SQL statement to the
MySQL server)
- It contains buffers to store the result (= tuples) of the query
- Store an
SQL statement (= query)
(by sending the SQL statement to the
MySQL server)
- The java.sql package
has many data structures
used to
process data
received from the SQL server
- Therefore:
- You must first create a Statement object before you can execute queries at the SQL server....
- How to
create
a Statement object
in JDBC:
Statement SQLstatement; // Ref. var. to a Statement object /* ---------------------------------------------- How to create a Statement object ---------------------------------------------- */ SQLstatement = SQLconnection.createStatement(); ^^^^^^^^^^^^^ The SQLconnection is a network connection object that was returned by getConnection()
- What is
achieved by the
SQLconnection.createStatement()
call:
-
Before
the execution of
the
SQLconnection.createStatement()
statement:
-
Before
the execution of
the
SQLconnection.createStatement()
statement:
-
Before
the execution of
the
SQLconnection.createStatement()
statement:
- Notes:
- Now (finally) we
can submit (= run) queries
using the Statement
object....
- You can use the
same
statement object
to
execute many
different queries
--- one query after another...
The Statement object will store the result of the most recently executed query
- Now (finally) we
can submit (= run) queries
using the Statement
object....