After setting `parquet.strings.signed-min-max.enabled` to `true` in
`ShowMetaCommand.java`, parquet-tools meta show min,max.
@@ -57,8 +57,9 @@ public class ShowMetaCommand extends ArgsOnlyCommand {
String[] args = options.getArgs();
String input = args[0];
Configuration conf = new Configuration();
+ conf.set("parquet.strings.signed-min-max.enabled", "true");
Path inputPath = new Path(input);
FileStatus inputFileStatus =
inputPath.getFileSystem(conf).getFileStatus(inputPath);
List<Footer> footers = ParquetFileReader.readFooters(conf,
inputFileStatus, false);
Result
row group 1: RC:3 TS:56 OFFSET:4
--------------------------------------------------------------------------------
field1: BINARY SNAPPY DO:0 FPO:4 SZ:56/56/1.00 VC:3
ENC:DELTA_BYTE_ARRAY -- ST:[min: a, max: c, num_nulls: 0]
For the reference, this was intended symptom by PARQUET-686 [1].
[1] https://www.mail-archive.com/commits@parquet.apache.org/msg00491.html
2018-01-24 10:31 GMT+09:00 Stephen Joung <step...@vcnc.co.kr>:
> How can I write parquet file with min/max statistic?
>
> 2018-01-24 10:30 GMT+09:00 Stephen Joung <step...@vcnc.co.kr>:
>
>> Hi, I am trying to use spark sql filter push down. and specially want to
>> use row group skipping with parquet file.
>>
>> And I guessed that I need parquet file with statistics min/max.
>>
>> ----
>>
>> On spark master branch - I tried to write single column with "a", "b",
>> "c" to parquet file f1
>>
>> scala> List("a", "b", "c").toDF("field1").coalesce(1
>> ).write.parquet("f1")
>>
>> But saved file does not have statistics (min, max)
>>
>> $ ls f1/*.parquet
>> f1/part-00000-445036f9-7a40-4333-8405-8451faa44319-c000.snappy.parquet
>> $ parquet-tool meta f1/*.parquet
>> file: file:/Users/stephen/p/spark/f
>> 1/part-00000-445036f9-7a40-4333-8405-8451faa44319- c000.snappy.parquet
>> creator: parquet-mr version 1.8.2 (build
>> c6522788629e590a53eb79874b95f6c3ff11f16c)
>> extra: org.apache.spark.sql.parquet.row.metadata =
>> {"type":"struct","fields":[{"name":"field1","type":"string",
>> "nullable":true,"metadata":{}}]}
>>
>> file schema: spark_schema
>> -----------------------------------------------------------
>> ---------------------
>> field1: OPTIONAL BINARY O:UTF8 R:0 D:1
>>
>> row group 1: RC:3 TS:48 OFFSET:4
>> -----------------------------------------------------------
>> ---------------------
>> field1: BINARY SNAPPY DO:0 FPO:4 SZ:50/48/0.96 VC:3
>> ENC:BIT_PACKED,RLE,PLAIN ST:[no stats for this column]
>>
>> ----
>>
>> Any pointer or comment would be appreciated.
>> Thank you.
>>
>>
>
