如何将两个参数传递给 IBM Bluemix 的 Node-Red 的 dashDB 查询元素

Question

我正在尝试将两个参数从 Bluemix 上的 Node-Red 流编辑器中的 dashDB 对象传递到 sql 查询。我的参数存储在 msg.fromDate 和 msg.toDate 中，我想将它们输入到 dashDB 节点的 "Parameter Marker" 中。当我只使用一个参数时，我只需在参数标记中键入 "msg.fromDate" 即可正常工作。在日志中我看到了这个：

2015-12-10T12:22:12.856+0100 [App/0] out Input node: pathToArray: msg,toDate 2015-12-10T12:22:12.856+0100 [App/0] out Input node: parameterValues: 2015-12-01

现在，当我尝试使用两个输入参数时，我在 "Parameter Marker" 中键入 "msg.toDate, msg.fromDate" 我在日志中收到此错误：

2015-12-10T12:26:01.271+0100 [App/0] out 10 Dec 11:26:01 - [error] [dashDB in:popular words] TypeError: Cannot read property 'fromDate' of undefined

2015-12-10T12:26:01.270+0100 [App/0] out Input node: pathToArray: msg,toDate, msg,fromDate

如何传递两个参数？

Answer 1

参数之间不能有引号，不确定添加引号只是为了格式化任务还是实际将其添加到参数中。

我用 function node 编写了一个简单的节点红色流来构建查询和 dashDB node 本身。

在我的 function node 中，我有以下查询：

msg.fromDate = '2011-04-12 00:00:00';
msg.toDate= '2015-03-12 00:00:00';
msg.payload = "SELECT COL2 FROM DASH104951.TESTDATE WHERE START >= ? AND END <= ?";
return msg;

在 dashDB node 我只有参数标记文本字段：

msg.fromDate,msg.toDate

一切正常。

如果你想将它导入到你自己的 node-red 应用程序中，这是我的 node-red 流程：

[{"id":"211a834b.dee57c","type":"inject","z":"197f318.fe680ce","name":"","topic":"","payload":"","payloadType":"none","repeat":"","crontab":"","once":false,"x":117,"y":115,"wires":[["7a23c994.85dc38"]]},{"id":"7a23c994.85dc38","type":"function","z":"197f318.fe680ce","name":"Build Query","func":"msg.fromDate = '2011-04-12 00:00:00';\nmsg.toDate= '2015-03-12 00:00:00';\nmsg.payload = \"SELECT COL2 FROM DASH104951.TESTDATE WHERE START >= ? AND END <= ?\";\nreturn msg;","outputs":1,"noerr":0,"x":325,"y":123,"wires":[["559c92e4.aa636c"]]},{"id":"24974090.db68c","type":"debug","z":"197f318.fe680ce","name":"dashDB query result","active":true,"console":"false","complete":"true","x":773,"y":125,"wires":[]},{"id":"559c92e4.aa636c","type":"dashDB in","z":"197f318.fe680ce","service":"dashDB-0a","query":"","params":"msg.fromDate,msg.toDate","name":"","x":548,"y":131,"wires":[["24974090.db68c"]]}]

Answer 2

我找到了这个问题的原因。看起来当我这样输入 "Parameter Marker" 时：

msg.toDate, msg.fromDate

它不起作用。就像这样它起作用了：

msg.toDate,msg.fromDate

换句话说参数之间的space打破了它！

如何将两个参数传递给 IBM Bluemix 的 Node-Red 的 dashDB 查询元素

How to pass two parameters to dashDB query element of Node-Red from IBM Bluemix

node-red

dashdb

ibm-cloud