alter table add partition hive
Uses of Hive ALTER TABLE Command. MSCK REPAIR is a resource-intensive query and using it to add single partition is not recommended especially when you huge number of partitions. XML Word Printable JSON. Details. If this post helps you, please consider to buy a cup of coffee for me. Is there a way to alter the table New partitions must be of the same type (LIST, RANGE or HASH) as existing partitions. Syntax: ALTER TABLE table_name PARTITION partition_spec RENAME TO PARTITION partition_spec; The following query is used to rename a partition: For more information: Support partial partition spec for certain ALTER PARTITION statements Support “alter table .. add/replace columns cascade” So, in the 5th query we run in the original test: ALTER TABLE test_external ADD … Partition column is a virtual column that does not exist on the file as a column. `Alter table recover partitions` is effectively an alias for `msck repair table`. The ALTER TABLE statement changes the structure or properties of an existing Impala table.. table_name: A table name, optionally qualified with a database name. Adding columns. If the table is created with option PARTITIONED BY it will be partitioned. Export. ADD PARTITION. Log In. Let us discuss the HIVE partition concept for the managed table first. Syntax. Solved: I am using hdp 2.4.2 (hive - 1.2.1.2.4). The ALTER TABLE statement changes the structure or properties of an existing Impala table.. SHOW PARTITIONS table_name [PARTITION(partition_spec)] [WHERE where_condition] [ORDER BY column_list] [LIMIT rows]; Conclusion. ALTER TABLE table_name ADD PARTITION (partCol = 'value1') location 'loc1'; ALTER TABLE table_name ADD PARTITION (partCol = 'value2') location 'loc2';... ALTER TABLE table_name ADD PARTITION (partCol = 'valueN') location 'locN'; Dynamic Partitions 动态分区. Add or drop table partition. Below command to add the partition to the table already created earlier. Most ALTER TABLE operations do not actually rewrite, move, and so on the actual data files. Without partitioning, any query on the table in Hive will read the entire data in the table. Make hive be able to read JSON. A 'S' lock on table and relevant partition is acquired when a read is being performed. In Impala, this is primarily a logical operation that updates the table metadata in the metastore database that Impala shares with Hive. Hive Alter Table - SQL ALTER TABLE statement is used to rename a table.The SQL ALTER TABLE statement is used to add, modify, or drop/delete columns in a table.It is used to alter a table in Hive. Description. HIVE-9430; NullPointerException on ALTER TABLE ADD PARTITION if no value given. To achieve this, we are going to add … Hive … ALTER TABLE lookup_table ADD COLUMNS (comments string); Replace all columns other than the partition columns. When I tried using the following hive command it gives me error. You can use ALTER TABLE with DROP PARTITION option to drop a partition for a table. ALTER TABLE ADD COLUMNS statement adds mentioned ... ALTER TABLE SET command is used for setting the SERDE or SERDE properties in Hive tables. If we have a large table then queries may take long time to execute on the whole table. Most ALTER TABLE operations do not actually rewrite, move, and so on the actual data files. The `msck repair table` command must be run from Hive. Type: Bug Status: Closed. HIVE Partition – Managed Table Partitioning. However if you had partitioned the existing table using “PARTITIONED BY” clause, then you will be allowed you add partition using the ALTER TABLE command. Change Column. Add Hadoop archive option to Hive table. Since every line in our data is a JSON object, we need to tell hive how to comprehend it as a set of fields. Do you want dynamic or static partitions? In Impala, this is primarily a logical operation that updates the table metadata in the metastore database that Impala shares with Hive. Hive Partitions is a way to organizes tables into partitions by dividing tables into different parts based on partition keys. msck repair table salesdata_ext; show partitions salesdata_ext; O/p: date_of_sale=10-27-2017. Hive> ALTER TABLE std_details ADD PARTITION (std_class=’1’); Once the above statement successfully executed, the partition added to std_db.std_details table. HIVE queries can take advantage of the partitioned data for better performance. ... None. Please refer to both the create and alter commands below: For partitions that are not compatible with Hive, use ALTER TABLE ADD PARTITION to load the partitions so that you can query their data. ALTER TABLE ADD statement adds partition to the partitioned table. Drop or Delete Hive Partition. ALTER TABLE some_table DROP IF EXISTS PARTITION(year = 2012); This command will remove the data and metadata for this partition. For the partition to reflect in the table metadata, we will either have to repair the table or add partition by using the alter command that we are discussing later.