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:: Esql Sample
Esql Sample
This sample consists of a command line SQL parser. SQL statements are filtered through a monitor and sent to the RDBMS.
Compiling
To compile the example:
- Launch EiffelStudio.
- Click Add project
- Browse to $ISE_EIFFEL\examples\store\esql\.
- Choose esql.ecf
- Choose the location where the project will be compiled, by default the same directory containing the configuration file.
- Choose the targe according to the installed DBMS.
- Click OK.
Running
This sample lets you interact with your database through a console.
First you have to enter the database connection information:
- For ODBC:
Database user authentication:
Data Source Name: handson
Name: smith
Password: mypass
Note: Name and Password are not required with ODBC. If you don't need Name and Password, you can simply hit Return when prompted.
- For Oracle:
Database user authentication:
Name: smith@HANDSON
Password: mypass
Note: You must specify the Oracle User Name and Net Service Name with the syntax <user>@<service> where <user> stands for the User Name and <service> stands for the Net Service Name.
Then you can enter standard SQL queries to interact with your database, for instance: SQL> select firstname, lastname from CONTACTS where lastname = 'Smith'
John Smith
SQL>
Note: Enter exit to quit the application.
Under the Hood
This sample showcases the use of the 3 basic classes to interact with your database:
- DB_CONTROL to connect and disconnect to your database.
- DB_SELECTION to perform 'select' queries.
- DB_CHANGE to perform SQL queries that output no result.
The whole sample code is contained in the root class:
- ESQL for Oracle.
- ESQL_ODBC for ODBC.