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Questions tagged [external-tables]

To be used for External tables. These tables don't necessarily have data in the data warehouse(or database directory).

Hive

An EXTERNAL table points to any HDFS location for its storage, rather than being stored in a folder specified by the configuration property hive.metastore.warehouse.dir(Location of default database for the warehouse). See also official Hive docs on Managed vs External Tables

Oracle

External tables allow Oracle to query data that is stored outside the database in flat files. The ORACLE_LOADER driver can be used to access any data stored in any format that can be loaded by SQL*Loader. No DML can be performed on external tables but they can be used for query, join and sort operations.

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How to truncate a partitioned external table in hive?

I'm planning to truncate the hive external table which has one partition. So, I have used the following command to truncate the table : hive> truncate table abc; But, it is throwing me an error stating : Cannot truncate non-managed table abc. Can…
fervent
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Create External table in Azure databricks

I am new to azure databricks and trying to create an external table, pointing to Azure Data Lake Storage (ADLS) Gen-2 location. From databricks notebook i have tried to set the spark configuration for ADLS access. Still i am unable to execute the…
anurag
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how to add columns to existing hive external table?

create external table demotable( column1 string, column2 string, column3 string) row format delimited fields terminated by '|' location '/data/demotable'; I create external table 'demotable' and the data in '/data/demotable' is like…
emhlbmc
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Why we need to move external table to managed hive table?

I am new to Hadoop and learning Hive. In Hadoop definative guide 3rd edition page no. 428 last paragraph I don't understand below paragraph regarding external table in HIVE. "A common pattern is to use an external table to access an initial dataset…
Raj
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External Tables vs SQLLoader

So, I often have to load data into holding tables to run some data validation checks and then return the results. Normally, I create the holding table, then a sqlldr control file and load the data into the table, then I run my queries. Is there any…
moleboy
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Does Hive's Create External Table copy data?

I have a Spark application that writes output files in Avro format. Now I would like that data to be available in Hive, because an application which would utilise that data can only do so through a Hive table. It is described here that one can do…
MetallicPriest
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Does DROP PARTITION delete data from external table in HIVE?

An external table in HIVE is partitioned on year, month and day. So does the following query delete data from external table for the specific partitioned referenced in this query?:- ALTER TABLE MyTable DROP IF EXISTS…
Dhiraj
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Unable to create external table using hive in aws EMR cluster where location pointing to some S3 location

I am trying to create an external table using hive service of AWS EMR cluster. Here, This external table is pointing to some S3 location. Below is my create table definition : EXTERNAL TABLE if not exists Myschema.MyTable ( columnA INT, …
Arun Joshi
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How do I parallel direct-path load using Oracle external tables?

Some years ago, Thomas Kyte said this (here): My favorite use of external tables: Load this really big file ASAP. In the past, setup the scripts to parallel direct path load. Coordinate the firing of said scripts. Review log files to make sure they…
Rudiger
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Hadoop - Create external table from multiple directories in HDFS

I have an external table that reads data from the HDFS location (/user/hive/warehouse/tableX) all files and created a external table in Hive. Now, let's assume there's some pre-partitioning of the data and all the previous files are spitted in…
Alg_D
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deleting null or __HIVE_DEFAULT_PARTITION__ in from hive external table and also from HDFS directory

i am trying to delete a null/HIVE_DEFAULT_PARTITION in from hive external table and also from HDFS directory but i couldn't delete it .. i have been to some other post regarding the same issue and i tried those even tho it is not showing any error…
sarath
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Netezza “[08S01] Communication link failure” Loading External Data

Am getting: ERROR [HY008] Operation canceled ERROR [08S01] Communication link failure When trying to upload external .txt file to Netezza database. I have done this in the past (just last week), but today receive this error. Am able to connect to…
thagraybush
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Change external table BADFILE, LOGFILE and DISCARDFILE parameters only

I have several external tables used to read file data into the DB each one for a particular file specification. For files of a single format a table is reused by pointing it at a new default directory and new file name. This is working fine except I…
Ollie
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Tasks - Generate Scripts in Azure Synapse Serverless SQL

I am working with an Azure Synapse Serverless SQL instance, connected via the most recent version of SSMS. I have several external tables defined over parquet files in an Azure Data Lake (Gen2). My question is how do I use the typical…
user24536
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BigQuery - CREATE EXTERNAL TABLE

How use CREATE EXTERNAL TABLE DDL statement in BigQuery? Another big datawarehouses solutions like SnowFlake and Hive Based(Presto, AWS Athena...) have it, and its so useful.
Émerson Engroff
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