Camel do while loop - while-loop

Question

I am trying to use camel dowhile loop.
I have two tables(ex : A,B) in datebase.
The goal is to insert into the data from A to B table by 500 lines for exemple. (The table is too big to use insert into at one time)
Here i want the loop to continue until insert into statement returns "0 rows".
<loop doWhile="true">
<!-- Stock last id of table B -->
<to uri="sql:{{export.table.b.last.fetched.id.query}}?dataSource=testDataSource&outputType=SelectOne" />
<setHeader headerName="last_fetched_id">
<simple>${body}</simple>
</setHeader>
<!-- Insert into query by using the last id limit 500 lines -->
<to uri="sql:{{export.table.a.insert.fetch.query}}?dataSource=testDataSource" />
<simple>${body} != 0</simple>
</loop>
I don't know what i do wrong in the codes. I have this error :
Caused by: org.xml.sax.SAXParseException: cvc-complex-type.3.2.2:
Attribute 'doWhile' is not allowed to appear in element 'loop'.

Answer 1

Looks like xml-validation error. You could double check that you've defined your loop correctly inside <route> and </route> tags after <from> tag. The xml-validation tests xml against the schemas (.xsd) defined in the xml-document.
Also the <simple>${body} != 0</simple> should be right after the <loop doWhile="true"> tag like shown in the documentation.
XML DSL - Documentation:
XML-DSL for Spring
XML-DSL for OSGi-Blueprint
As for sql queries select operations return body of type List<Map<String, Object>> containing query results and number of rows is stored to CamelSqlRowCount header. With update operations null body is returned and number of rows affected is stored CamelSqlUpdateCount header,
Result of the query
Headers
As for the loop you you could try setting the body to the value of CamelSqlUpdateCount:
<setBody>
<header>CamelSqlUpdateCount</header>
</setBody>
Alternatively if you're using direct consumer endpoint you could remove the loop altogether and use recursion instead by just calling the route again at the end until CamelSqlUpdateCount is zero.