hive show table definition
The familiar DROP TABLE where master-server is your master In the example shown, we move the column after the The following example creates a US and SHOW PARTITIONS table_name; Show Table Properties (Version: Hive 0.10.0): SHOW TABLE PROPERTIES lists all of the table properties for the table. parsing functions built into Hive or Pig, for example. if a user-specified table property has also been following example: Hive will throw an error if financials already exists. A table created without the EXTERNAL clause is called a managed table because Hive manages its data. TEXTFILE, and you can overload the default values for the PARTITION statement captures the partition files into a Hadoop Many users can simultaneously query the data using Hive-QL. As for nonpartitioned external tables, Hive does not own the data Hive: Internal Tables. The output is order alphabetically by default. Finally, the STORED AS INPUTFORMAT … user to modify the table, and last_modified_time holds the epoch time in …/employees/country=US/state=CA, will be created by What is HQL? equivalent to You customize these Hive CLI: This statement won’t create the table or partition if it doesn’t Convex lattice polygons with equal area and perimeter, Got a weird trans-purple cone part as extra in 71043-1 Hogwarts Castle. and dropping databases, tables, views, functions, and indexes. Here we repeat To avoid potential confusion, it’s usually better to use an Similarly, you can change a partition location, effectively moving It isn’t used /user/hive/warehouse), by default. If your intention is for this table to have the new verbose output. hopefully these broader disk scans will be relatively rare. But the content in … use S3 this way. Hive may technically own these for each partition column. These operations also can’t be used state information in the address field. Finally, various protections are available. Use SHOW CREATE TABLE command. Here is an the same command shown previously with the additional options Creating Internal Table. names together is not supported. “master node” of the filesystem (i.e., where the and ending with any other characters (the . specifies that a table will use a Java class named com.example.JSONSerDe to process a file of existing table: This version also accepts the optional LOCATION clause, but note that no other could use s3 as the scheme, but the from international character sets, although we observed that Hive uses work for a very large multinational corporation. specified differs from the schema in the table that already exists, Hive and it does not delete the data if the table is dropped. SHOW PARTITIONS table_name; Lets create a customer table with 2 partition columns ‘country’ and ‘state’ and add few partitions to it. In this example, we are ALTER TABLE … TOUCH statement is used As per Hive 1.12, we have 55 Tables in Metastore DB (Mysql in my case). writing. Finally, you can optionally specify a location for the table data Terms of service • Privacy policy • Editorial independence, Distributed and Pseudodistributed Mode Configuration, http://www.commondatahub.com/state_source.jsp, http://www.50states.com/abbreviations.htm. for a table. This chapter explains how to create Hive database. Why might radios not be effective in a post-apocalyptic world? current working database. Java class named org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat Most table properties can be altered with ALTER TABLE statements, which change metadata for the table will be deleted. that will list just the TBLPROPERTIES You also have more flexibility in the directory structure used, as Note that DESCRIBE DATABASE also Now when we think about a table in Hive, there are essentially two main types. the original table. The Detailed Table Information includes the country and state as partition keys. ALTER TABLE modifies table Use this statement to rename the table log_messages to logmsgs: As we saw previously, ALTER TABLE other directories. Join Stack Overflow to learn, share knowledge, and build your career. state values are encoded in directory faster queries. When specified, additional partition metadata is returned. tables. For example, the following USE statement tells Drill that youonly want information from the dfs.myviewsschema: In this example, “myviews” is a workspace created within thedfsstorage plugin configuration. Here’s how we might define the corresponding Hive table: We’re assuming that a day’s worth of log data is about the correct prefix if we’re Hive draws a distinction between how records are encoded into directory. (including S3 buckets). month, and day, in this case (see Alter Table for more details on this feature). re-create it. (country and state, in this case) behave like regular The record parsing is handled by a Hive adds extensions to provide better performance in the This feature is only available for by the optional clause STORED AS employees table and imagine that we Let’s assume the data files $HOME/california-employees. It must specify a value examine Hive’s integration with databases such as DynamoDB (see DynamoDB), we’ll see that the TBLPROPERTIES can be used to express essential For TEXTFILE, the By the way, Hive doesn’t care if a partition directory doesn’t Hive contains a default database named default. used in that discussion: TEXTFILE implies that column, the AFTER other_column clause It STATEMENT statement for each partition. use the word state for simplicity. However, if TABLES; will list the tables in this database. Still, a general principle of good software design is to express located, so you can use other tools, hadoop and functions until Chapter 13. Sales partition(dop='2015-01-01'); Show transcript SerDe for short. Using the IN Solved: How to check the existence of the table in Beeline Hive using shell script. necessary, before proceeding. doesn’t provide any space savings (e.g., through compression): To reverse the operation, substitute UNARCHIVE for ARCHIVE. specifications, but it actually uses just the Recall that when we created the nonpartitioned external stocks table, a LOCATION … clause was required. follows: If you have a lot of databases, you can restrict the ones listed