Do you also want to rename VIEW? I moved a specific database from one cluster to another with all the related data and tables. Is there a way to alter the location that a database points to? If a particular property was already set, this overrides the old value with the new one. Not allowed to alter the directory location or database name. The ALTER DATABASE... SET LOCATION statement does not move the contents of the database's current directory to the newly specified location. Ok, so here is a scenario. ALTER TABLE command can be used to perform alterations on the tables. https://t.co/9lmsA6lhRJ, Proud to see @SnowflakeDB on the #FCMostInnovative Companies list for 2021! I am able to access all the tables without any issues. Mostly ALTER can be used to alter database or schema properties and owner change. The default database can not be altered in the Hive because it is restricted. ALTER TABLE SET command is used for setting the SERDE or SERDE properties in Hive tables. Hive>use database; Hive>grant all on table table_name to role os_user_name with grant option; By this "os_user_name" only can able to access, other wont able to see the tables. Why do many occupations show a gender bias? Doubts related to speed of sound in different mediums. Have you checked the Hive DB’s metadata information in your backend database? May be what you told will not support in handling existing views. After some trial and error, I learned Hive does not support the following two conditions when running an ALTER on a database. ALTER DATABASE hql SET DBPROPERTIES('database usage'='Hive SQL tutorials. Your email address will not be published. ALTER Statement on HIVE Table. It has worked me at Hive permission level at USER. rename hive table ALTER TABLE tbl_nm RENAME TO new_tbl_nm; In the above statement the table name was changed from tbl_nm to new_tbl_nm. We can. Thank you. Is it more than one pound? You can use simple create database database_name command to create database … Hadoop Troubleshooting Guide - Eric's Blog, Locate Hive Tables with Same HDFS Location, Unable to run Hive CTAS query if user has no write permission on current database, Show Create Table Output Truncated for VIEW in Hive, Insert Unicode Data Into MySQL Database in PHP. New tables will be put at the new location of the database. hive> ALTER TABLE employee ADD COLUMNS ( > dept STRING COMMENT 'Department name'); JDBC Programm. I will not be updating this blog anymore but will continue with new contents in the Snowflake world! Adding partition- Syntax - hive> ALTER TABLE employee ADD PARTITION(year =‘2013’) location ‘/2012/part2012’; Dropping partition - Syntax - hive>ALTER TABLE employee DROP [IF EXISTS] PARTITION (year=‘2013’); 20. id, name, dept, year 1, Mark, TP, 2012 2, Bob, HR, 2012 3, Sam,SC, 2013 4, Adam, SC, 2013 21. Effects of time dilation on our observations of the Sun. jdbc:hive2://>ALTER TABLE employee RENAME TO employee2; Drop Table. Apache Hive is often referred to as a data warehouse infrastr u cture built on top of Apache Hadoop. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. ALTER TABLE is a logical operation that updates the table metadata in the metastore database that shares with Hive. See https://issues.apache.org/jira/browse/HIVE-1537 and https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL#LanguageManualDDL-AlterTable/PartitionLocation for details regarding database and table locations. I tried doing so, changed the name of the .db directory to the new database name and guess what, when I use the newly renamed database, use any table and run a select * query on it, it doesn’t return any value. The file operations need to perform manually corresponding physical filesystem operations. Can you tell the HMS db location as i was not able to found that in warehouse directory. Firstly thanks for visiting my site and asking questions. You will also have to change the location of each of the existing tables using the above alter. Update Hive Partition You can use the Hive ALTER TABLE command to change the HDFS directory location of a specific partition. Drop Table is used to Drop the table from a Hive database. jdbc:hive2://>DROP TABLE employee2; jdbc:hive2://>DROP TABLE emp.employee2; jdbc:hive2://>DROP TABLE IF EXISTS employee2 PURGE; Conclusion . SCHEMA in ALTER added in Hive 0.14.0. Alter Table. View my verified achievement from @SnowflakeDB. Your email address will not be published. Assign any new (key, value) pairs into DBPROPERTIES; Set owner user or role to the Database; But below are its limitations. This article explains how to rename a database in Hive manually without modifying database locations, as the command: ALTER DATABASE test_db RENAME TO test_db_new; still does not work due to HIVE-4847 is not fixed yet. This utility can be used to initialize Apache Atlas with databases/tables present in Apache Hive. Here are the illustrated steps to change a custom database location, for instance "dummy.db", along with the contents of the database. Alter Databases. 2. I was able to rename my database name by following the steps which you have provided. Drop database DROP (DATABASE|SCHEMA) [IF EXISTS] database_name [RESTRICT|CASCADE]; Here we will discuss how we can change table level properties. Der JDBC-Programm, um eine Spalte zu einer Tabelle hinzufügen ist unten angegeben. Instead, a new convention has been introduced that Kudu table names must be in the format
.. HIVE DATA TYPES; Hive Table Creation; HIVE ALTER TABLE; Hive Table Partition; Hive Split a row into multiple rows; HIVE SHOW PARTITIONS; Scala Tutorial For Spark. Hadoop Hive alter database is a statement used to change the properties of a databases in Hive. ALTER TABLE table_name CHANGE old_col_name new_col_name new_data_type Here you can change your column name and data type at a time. Connect and share knowledge within a single location that is structured and easy to search. The database framework supports all the regular commands like create, drop, alter, use database. The following queries rename the column name and column data type using the above data: Click here for instructions on how to enable JavaScript in your browser. How long would it take for inbreeding issues to arise for a family that practiced inbreeding? By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy. ALTER TABLE does not actually rewrite, move, etc, on the actual data files. thanks for trying to help, but what I am looking for is - if I have already created a database, and now I want to move it to a different directory in HDFS. With Databases, You can have logical separation of tables, table names, and even where data is going get store by default. Apache Atlas provides a command-line utility, import-hive.sh, to import metadata of Apache Hive databases and tables into Apache Atlas. http://gaganonthenet.com/2015/02/23/hive-change-location-for-database-or-schema/, https://issues.apache.org/jira/browse/HIVE-1537, https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL#LanguageManualDDL-AlterTable/PartitionLocation, State of the Stack: a new quarterly update on community and product, Podcast 320: Covid vaccine websites are frustrating. Sci-fi film where an EMP device is used to disable an alien ship, and a huge robot rips through a gas station. You can add or remove the database comments, properties etc by using alter database statements. How worried should I be about this cough? In the Below screenshot, we are creating a table with columns and altering the table name. In the Hive, the database framework is developed by Facebook to analyze structured data or semi-structured data. The RECOVER PARTITIONS clause automatically recognizes any data … In this Most Used Hive DDL … What's the map on Sheldon & Leonard's refrigerator of? You can either drop the tables first or append the CASCADE keyword to the command, which will cause the Hive to drop the tables in the database first: hive> DROP DATABASE IF EXISTS financials CASCADE; If you don't want to change col_name simply … Using partition, it is easy to query a portion of the data. myoung. Mark as New; Bookmark; Subscribe; … You need to use the following ALTER TABLE syntax: ALTER TABLE table_name CHANGE column_name column_name newType To break it down, you are: Making a change to the table: ALTER TABLE; Defining what table you are changing: table_name; Defining what column you will change: CHANGE column_name; Defining the change (you can also change column_name hence the double mention): column_name … To allow me to help, can you please give me a bit more context on what is broken for VIEW? Sorry about the late response, I was on holiday in the last few weeks, and now just back to work. Syntax for changing Database Properties: ALTER (DATABASE|SCHEMA) database_name SET DBPROPERTIES (property_name=property_value,...); To learn more, see our tips on writing great answers. Join Stack Overflow to learn, share knowledge, and build your career. My understanding of HIVE-1537 is that you will have to update the database location and manually move the files on HDFS. Save my name, email, and site URL in my browser for next time I post a comment. We can also use the database layer with different Hadoop components like Hbase, Kafka, spark, different streaming tools, etc. We can’t unset any property using Alter command Do "the laws" mentioned in the U.S. Oath of Allegiance have to be constitutional? You will also have to change the location of each of the existing tables using the above alter. 9,201 Views 2 Kudos Highlighted. In Hive, we can add one or more columns in an existing table by using the following signature: - Alter table table_name add columns (column_name datatype); Let's see the schema of the table. Thus, databases are an implicit part of the Kudu table name. This developer built a…, Create HIVE partitioned table HDFS location assistance. rev 2021.3.12.38768, Stack Overflow works best with JavaScript enabled, Where developers & technologists share private knowledge with coworkers, Programming & related technical career opportunities, Recruit tech talent & build your employer brand, Reach developers & technologists worldwide. Please tell me how to fix this. ALTER SCHEMA was added in Hive 0.14 (HIVE-6601). Thanks for contributing an answer to Stack Overflow! Note that there is no impact on the data that resides in the table. Now, I want to rename the database. New tables will be put at the new location of the database. To rename a Table use ALTER TABLE command. The database and schema are interchangeable. However, I found a link to a workaround that involves a direct DB update to the Hive Metastore and simply moving the directory on HDFS. Reply. Currently you have JavaScript disabled. You will have to manually move the directories on HDFS and update the table locations. Click here for instructions on how to enable JavaScript in your browser. I want to turn an equality statement into a function, C++ syntax understanding issue for 'using', Retaining permissions when copying a folder. Asking for help, clarification, or responding to other answers. So, my question here is, wouldn’t I also will have to change the name of the directory under /app/hive/warehouse?? Hide the source code for an Automator quick action / service. Let's see the data of columns exists in the table. Why might radios not be effective in a post-apocalyptic world? Syntax--Set SERDE Propeties ALTER TABLE table_name [PARTITION part_spec] SET SERDEPROPERTIES (key1 = val1, key2 = val2,...) ALTER TABLE table_name [PARTITION part_spec] SET SERDE serde_class_name [WITH … site design / logo © 2021 Stack Exchange Inc; user contributions licensed under cc by-sa. The following table contains the fields of employeetable and it shows the fields to be changed (in bold). alter database set DBPROPERTIES('hive.warehouse.dir'=''); alter database set DBPROPERTIES('location'=''); alter database set location ''; The first two alter statements just changed the DB properties, however the database still points to the same location; while the third alter statement gave me semantics error. How hard does atmospheric drag push on the ISS? Creating table guru_sample with two column names such as "empid" and "empname". For the DB rename to work properly, we need to update three tables in the HMS DB. However, they are very useful on large clusters or with multiple teams/individuals using Hive for different reasons. Sorry about the late response, I have updated my article to also cover the VIEW in Hive when renaming database. What do you roll to sleep in a hidden spot? @FastCompany recognizes how… https://t.co/KFiE79SGBT, Snowflake Guide New Post: TIMESTAMP Function Returns Different Results When Sorted By Different Direction https://t.co/c37Jq0qESo. Tables created before the alter will live in the previous location. The below example update the state=NC partition location from the default Hive store to a custom location /data/state=NC. There are few views which are not working after updating the database name as they are still looking for the old database name. '); Output: OK Use database USE database_name; Example: USE hql; Output: OK. Thank you for the steps. For every successfully created database, the Alteration can be done as per the user requirement. Guru. ALTER DATABASE in Hive The ALTER DATABASE statement in Hive is used to change the metadata associated with the database in Hive. Is there an engine evaluation technique that factors in 'time'? Or if you use Cloudera Manager, you can go to CM home page > Hive > Configuration > search for “database” and you can see the host, username etc, but password will not be visible, you will need to check with your system admin. My understanding of HIVE-1537 is that you will have to update the database location and manually move the files on HDFS. If a diode has capacitance, why doesn't it block the circuit after some time? Lets check it with an example. With Alter table command, we can also update partition table location. Now let’s add 2 new columns to the table and load a file containing data in 4 columns: ALTER TABLE airfact ADD COLUMNS (flight STRING, time STRING); LOAD DATA LOCAL INPATH 'airfact2.txt' INTO TABLE airfact; The sample airfact2.txt data file content: SFO JFK Delta 2240 9:15p ORD LAX Virgin America 241 5:35p Now if you retrieve the data from airfact table, Hive returns NULL values … To alter the location of a table, you can run ALTER TABLE SET LOCATION "/path/to/new/location"; This can also be applied at the partition level. How to outline the union of an annulus and a rectangle in TikZ? The HMS DB is configured in hive-site.xml file for HMS, so you can examine this configuration file to determine what’s the backend DB configurations. Making statements based on opinion; back them up with references or personal experience. Scala Programming Features. Displaying tables present in guru99 database. Required fields are marked *. Creating Database. How to point one Hive Table to Multiple External Files? To automatically detect new partition directories added through Hive or HDFS operations: In Impala 2.3 and higher, the RECOVER PARTITIONS clause scans a partitioned table to detect if any new partition directories were added outside of Impala, such as by Hive ALTER TABLE statements or by hdfs dfs or hadoop fs commands. https://cwiki.apache.org/confluence/display/Hive/Hive+Transactions We can modify multiple numbers of properties associated with the table schema in the Hive. The above command sets current database to hql. It's simple usually to change/modify the exesting table use this syntax in Hive. What is the best way to turn soup into stew without using flour? How can that be achieved ? Created 08-19-2016 12:20 PM. Re: Setting a permission in hive databases. alter database; alter table (skewed table information, stored as, protection is not supported) alter view; Importing Hive Metadata. ALTER TABLE log_messages PARTITION (year = 2019, month = 12) SET LOCATION '/maheshmogal.db/order_new/year=2019/month=12'; 1. My views are not working now. Alteration on the database is made to change its existing properties or characteristics. Do you want to change hive warehouse directory? See my updated answer, the previous one I had was incorrect and would not work. DATABASE or SCHEMA is same thing in behavior. Would really appreciate if you could help me resolve this. In order to post comments, please make sure JavaScript and Cookies are enabled, and reload the page. Not allowed to delete or unset the db properties which have been defined before. Updating & Renaming Partitions in Hive Tables. If you run “SELECT * FROM DBS WHERE NAME = ‘{db_name}'”, is the path correct? 1. My new Snowflake Blog is now live. You might also want to check the table’s metadata “SELECT * FROM TBLS WHERE TBL_NAME = ‘{table_name}'” and confirm that the table’s metadata is correct. It does not change the locations associated with … Apache Hive comes with an already created database with the name default. By default, Hive won’t permit you to drop a database if it contains tables. HIVE ALTER Table Syntax hive> ALTER TABLE emp RENAME TO employee;--Rename Table Name hive> ALTER TABLE emp CHANGE name firstname String;--Rename Column Name hive> ALTER TABLE emp CHANGE sal sal Double; -- Rename data types hive> ALTER TABLE emp ADD COLUMNS (dno INT COMMENT 'Department number'); -- Add column name hive> ALTER TABLE emp REPLACE COLUMNS … The syntax for Hive alter database statement is as follows: ALTER (DATABASE|SCHEMA) database_name SET DBPROPERTIES (property_name=property_value,...); Hive databases are nothing more than namespace for tables. By default, the location for default and custom databases is defined within the value of hive.metastore.warehouse.dir, which is /apps/hive/warehouse. We can alter the databases with Alter command in hive but it provides very minimal alterations. Only tables created after the alter will be put in the new location. As I am using MySQL, I will use MySQL query example here, change accordingly based on your DB type: DBS table, this table holds the information about Databases in Hive: This article explains how to rename a database in Hive manually, ©2021 Hadoop Troubleshooting Guide - Eric's Blog, Impala nested inline view produces incorrect result when referencing the same column implicitly, Hive Dynamic Insert Query Only Uses 1 Reducer out of Thousands of Reducers. Table Operations such as Creation, Altering, and Dropping tables in Hive can be observed in this tutorial. HIVE database does not exist SemanticException 10072, External Hive table from AVRO files says it has no data, Sqoop / Hive for CCA175: getting table AlreadyExistsException, Hive: modify external table's location take too long, cannot recognize input near database SET LOCATION in alter database statement in hive. Hive provides us the functionality to perform Alteration on the Tables and Databases. Originally developed by Facebook to query their incoming ~20TB of data each day, currently, programmers use it for ad-hoc querying and analysis over large data sets stored in file systems like HDFS (Hadoop Distributed Framework System) without having to know specifics of map-reduce. http://gaganonthenet.com/2015/02/23/hive-change-location-for-database-or-schema/.