About Nevo

Nevo · ‎10-10-2017

Huh... the SHOW CREATE TABLE indicated STORED AS TEXTFILE. I'm going to guess this is a Stupid User Trick and that I mistyped something. Dropping and recreating the table appears to have resolved the issue, although I had limited time to look at it today. Thanks for the help, everyone. Getting the SHOW CREATE TABLE hint was key. I learned something today!

Nevo · ‎10-10-2017

Well, even to an idiot like me who's never used Impala, this is suspicious.... EXPLAIN SELECT * FROM nrtest2; 1 Per-Host Resource Reservation: Memory=0B 2 Per-Host Resource Estimates: Memory=10.00MB 3 WARNING: The following tables are missing relevant table and/or column statistics. 4 default.nrtest2 5 6 PLAN-ROOT SINK 7 | 8 01:EXCHANGE [UNPARTITIONED] 9 | 10 00:SCAN HDFS [default.nrtest2] 11 partitions=1/1 files=0 size=0B How do I get Impala to tell me where on disk it's looking for files? DESCRIBE gives me the schema for the table but not the location of the table.

Nevo · ‎10-09-2017

I have a Parquet file that has 5,000 records in it. I moved it to HDFS and ran the Impala command: CREATE EXTERNAL TABLE mytable LIKE PARQUET '/user/hive/MyDataFolder/MyData.Parquet' STORED AS PARQUET LOCATION '/user/hive/MyDataFolder'; Impala creates the table, and I can see the correct schema in Hue. I know that this Parquet file has 5,000 records in it. I know this because I put 5,000 records in it when I created it, and because I can query it with Drill and see 5,000 records. However, when I perform a query in Impala: SELECT * FROM mytable; I get back 0 rows. Why? How do I tell Impala to 'see' those 5,000 records in the file I gave it?

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Re: Create Impala table from existing Parquet file

Re: Create Impala table from existing Parquet file

Re: Create Impala table from existing Parquet file

Create Impala table from existing Parquet file