任務(wù):給根節(jié)點(diǎn)加上屬性。
步驟:
仍然是使用一個(gè)MQ input節(jié)點(diǎn),一個(gè)MQ output節(jié)點(diǎn)和一個(gè)Compute節(jié)點(diǎn),Compute節(jié)點(diǎn)的ESql如下:
CREATE COMPUTE MODULE flow_Compute
CREATE FUNCTION Main() RETURNS BOOLEAN
BEGIN
SET OutputRoot = InputRoot;
DECLARE Count Integer 0;
SET Count=CARDINALITY(InputRoot.XML.employees.employee[]);
SET OutputRoot.XML.employees.(XML.Attribute)count=Count;
RETURN TRUE;
END;
END MODULE;
上圖粗體部分為關(guān)鍵,它的作用是給employees節(jié)點(diǎn)增加了一個(gè)屬性Count.
輸入的XML分別如下:
<employees><employee><id>001</id><name>張飛</name><age>28</age></employee><employee><id>002</id><name>關(guān)羽</name><age>29</age></employee><employee> <id>003</id><name>趙云</name><age>30</age></employee></employees>
輸入和輸出的XML分別如下:
<employees count="3"><employee><id>001</id><name>張飛</name><age>28</age></employee><employee><id>002</id><name>關(guān)羽</name><age>29</age></employee><employee> <id>003</id><name>趙云</name><age>30</age></employee></employees>工程下載: