Thanks a lot. I understand now.

On 2020/06/27 02:45:52, Gary Li <[email protected]> wrote: 
> Hi,
> 
> If you use year=xxx/month=xxx folder structure, you can use Dataset<Row>
> df=
> spark.read().format("hudi").schema(schema).load(<base_path>+<table_name>).
> Without a glob postfix, Spark can automatically load the partition
> information, just like regular parquet files.
> https://spark.apache.org/docs/latest/sql-data-sources-parquet.html#partition-discovery
> 
> If you use something like 2020/06, you may need to build the glob string
> and add it to the load() to skip the unnecessary partitions. e.g.
> .load(<base_path>+<table_name>+"2020/{05,06}")
> 
> Or list one parquet file from different partitions and use a map function
> to load 1 row from each path with a limit clause.
> 
> On Fri, Jun 26, 2020 at 8:33 AM Tanuj <[email protected]> wrote:
> 
> > Hi,
> > We have created a table with partition depth of 2 as year/month. We need
> > to read data from HUDI in Spark Streaming layer where we get the batch data
> > of say 10 rows which we need to use to read from HUDI. We are reading it
> > like -
> >
> > // Read from HUDI
> > Dataset<Row> df=
> > spark.read().format("hudi").schema(schema).load(<base_path>+<table_name>+"/*/*")
> >
> > //Apply filter
> >
> > df=df.filter(df.col("year").isin(<vals>).filter(df.col("month").isin(<vals>)).filter(df.col("id").isin(<vals>));
> >
> > Is it the best way to read the data ? Will HUDI take care of just reading
> > from the partitions or we need to take care of ? For eg. If I need to read
> > just 1 row we can build the full path and then read which will read the
> > parquet file from that partition quickly but here our requirement is to
> > read data from multiple partitions.
> >
> >
> >
> 

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