Forms: Database Exporter

A Database Exporter allows data held in a Stream to be written to a Datasource.

Form: Database Exporter Details

The Database Exporter form contains a number of tabs:

Form Icons

The form provides the standard form icons.

Tab: Database Exporter Details

The following fields are configured on the Details tab:

Tab: Database Exporter Query String

The following fields are configured on the Query String tab:

Query String Description

Database Exporters can be set up to update a database using either a plain SQL query or PL/SQL. If you want to use PL/SQL tick the box Uses PL/SQL.

Plain SQL query

Enter an insert or update query just as you would to edit the database directly. The only important difference when creating queries in CenterView is that expressions must be enclosed in curly braces i.e. start with a '{' and end with '}'. This includes referencing an attribute name from the input Stream - which is just a simple expression.

Note that when exporting a stream attribute field of Type 'TrueFalse', this attribute must be mapped correctly to the corresponding underlying database column it is being exported into. An 'if' style expression should be used in the query string to transform the TrueFalse value into the appropriate database column. Mapping to a single character database column - {if(aTrueFalseStreamAttribute,'T','F')}
Mapping to a single numeric database column - {if(aTrueFalseStreamAttribute,1,0)}

The other difference between entering a query in CenterView and submitting a query to the database directly is that you must not include the standard SQL statement terminator, e.g. a semi-colon, at the end of your query.

insert into INTL_CODES values({Operator}, {Code})

If we have an input Stream containing a list of international codes, with attributes Operator and Code, this query will insert all data from the input Stream into a database table INTL_CODES.

insert into INTL_CODES values({Operator}, {Code}, {toDate(StartDate)})

The table INTL_CODES also includes a date, START_DATE, which we will populate using the attribute StartDate in the input Stream. In the Stream, this date is stored as a string in the format YYYYMMDD. In the query above, we have converted this string to a date using a CenterView expression.

insert into INTL_CODES values({Operator}, {Code}, to_date({StartDate}, 'yyyymmdd'))

This query performs the same inserts as the previous example, but in this case we are converting the StartDate string value to a date using a database function.

PL/SQL

As for a plain SQL query, you can write PL/SQL just as you would to run against the database directly - but putting any CenterView expressions in curly braces i.e. starting with a '{' and ending with '}'.

declare v_count number;
begin
	select count (1)
	into v_count
	from INTL_CODES
	where operator = {Operator} and code = {Code};
 
	if (v_count = 0)
	then
		insert into INTL_CODES
		values( {Operator}, {Code}, {toDate(StartDate)} );
	else
		update INTL_CODES set START_DATE = {toDate(StartDate)}
		where operator = {Operator} and code = {Code};
	end if;
end;

In this example we are loading international codes into a database, as in the plain SQL examples. Here, we want to insert a new value if no value already exists in the table for the Operator/Code combination; otherwise we will edit the existing record with the START_DATE of the current value that we have read from the input stream.

Tab: Database Exporter Advanced

The following fields are configured on the Advanced tab:

Tab: Input Multiplier

The following fields are configured on the Input Multiplier:

See Also

• Forms