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The data package (currently under development) provides a framework for access to SQL databases. You will need to provide JDBC drivers for the database you intend to use. The only database that has so far been tested with this package is InstantDB, an all-Java SQL database.

This package uses a 'middle tier' persistence framework to manage a local cache of records, avoiding the need to go to the SQL database for every operation. It also provides a cleaner mechanism for taking care of errors as well as dealing with the interface to different database types. Here is some documentation about the Java classes used.

These are the keywords supplied for database operations:

clear	Clear the fields of a record.
commit	Commit changes to the database.
create	Create a new record.
database	Connect to a database.
decrypt	Decrypt a record from a string.
delete	Delete a record.
encrypt	Encrypt a record to a string.
get	Get one or more records.
insert	Insert a record into the database.
new	Start a new transaction.
read	Read in an XML file.
record	Declare a record variable.
set	Set field values or attributes.
specification	Declare the specification for a table type.
sql	Issue an SQL command to the database.
update	Update a record in the database.

Numeric values
String values
Conditional expressions

These values can be used in either a numeric or string expression:

field {fieldname} of {record}
Returns the contents of the field specifed of record {record}.

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These values can be used in a string expression:

the status
Returns a string comprising a result code from the last operation. If no error occurred this string is "OK". Other result codes are:

*** to be implemented ***

encrypted {record}
Returns a string comprising all the fields of the record encrypted using the key held in the record. See encrypt and set.

{record}
Returns a string comprising all the fields of the table holding records of this type, encoded as an XML string.

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These are the conditional functions available for use with the data package:

[no] more {record}
Returns true if there are (or are not) more records yet to be read in the result set returned by the last query on record {record}.

{record} exists/does not exist
Returns true if a record does (or does not) exist having the ID of the one named.

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