XML representation of queries


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XML documents can contain query instructions with conditions for the records to be retrieved. In this case, the XML document complies with the Query By Form (QBF) definition.

Syntax

<Query>
<Table Name="value">
<Column Name="value" Condition="value"
Order-by-seqno="value" Order-by-direction="value"/>
<Column Name="value" Order-by-seqno="value"/>
<Column Name="value" Condition="value"/>
</Table>
</Query>
  • Underscores are replaced by two underscores.
  • Table names and column names are always in uppercase.

Furthermore:

  • The root element of the XML document is <Query>.
  • The <Table> element has a Name attribute that specifies the table to be queried. An XML document can only query data from one table.
  • The <Column> elements contain the query conditions. You can only query those columns for which the Query Allowed attribute has been set to Yes.
  • By specifying Order-by-seqno and Order-by-direction attributes, the order of the records retrieved from the database can be determined. Order-by-seqno must have a numeric value.
  • The columns are added to the ORDER BY clause of the query in the order of the Order-by-seqno. The Order-by-direction attribute can have value "Ascending" (default) or "Descending".

Example

<Query>
<Table Name="value">
<Column Name="value" Condition="value"
Order-by-seqno="value" Order-by-direction="value"/>
<Column Name="value" Order-by-seqno="value"/>
<Column Name="value" Condition="value"/>
</Table>
</Query>
<Query>
<Table Name="PERSON">
<Column Name="FAMILY_NAME" Condition="Jo%"/>
</Table>
</Query>

 


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