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1024programmer Java MongodbMapreduce output option is replace to a Collection but there is no such result Collection TAT

MongodbMapreduce output option is replace to a Collection but there is no such result Collection TAT

author: admin Post: November 17, 2023 28read 0Comment

Mapreduce

When I was doing MR, I wanted to write the results into a new collection. In fact, I have done it before, but when I In my mind, I always seem to be unable to write in, so bad!

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// …. More code

Try {
br />
this.dbc, MapString,

ReduceString,

dbtemp,

MapReduceCommand.OutputType.REPLACE,

query);

cmd.setFinalize(Finalize);

//…more code

The formal parameters of MapReduceCommand are as follows

1	public MapReduceCommand(com.mongodb.DBCollection inputCollection, java.lang.String map, java.lang.String reduce, java.lang.String outputCollection, com.mongodb.MapReduceCommand.OutputType type, com.mongodb .DBObject query) { /* compiled code */ }

I hope there are friends who have done mongo to discuss together

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