Skip to content

Latest commit

 

History

History
198 lines (143 loc) · 17 KB

apache-hive-catalog.md

File metadata and controls

198 lines (143 loc) · 17 KB
title slug date keyword license
Apache Hive catalog
/apache-hive-catalog
2023-12-10
hive catalog
This software is licensed under the Apache License version 2.

Introduction

Apache Gravitino offers the capability to utilize Apache Hive as a catalog for metadata management.

Requirements and limitations

  • The Hive catalog requires a Hive Metastore Service (HMS), or a compatible implementation of the HMS, such as AWS Glue.
  • Gravitino must have network access to the Hive metastore service using the Thrift protocol.

:::note The Hive catalog is available for Apache Hive 2.x only. Support for Apache Hive 3.x is under development. :::

Catalog

Catalog capabilities

The Hive catalog supports creating, updating, and deleting databases and tables in the HMS.

Catalog properties

Besides the common catalog properties, the Hive catalog has the following properties:

Property Name Description Default Value Required Since Version
metastore.uris The Hive metastore service URIs, separate multiple addresses with commas. Such as thrift://127.0.0.1:9083 (none) Yes 0.2.0
client.pool-size The maximum number of Hive metastore clients in the pool for Gravitino. 1 No 0.2.0
gravitino.bypass. Property name with this prefix passed down to the underlying HMS client for use. Such as gravitino.bypass.hive.metastore.failure.retries = 3 indicate 3 times of retries upon failure of Thrift metastore calls (none) No 0.2.0
client.pool-cache.eviction-interval-ms The cache pool eviction interval. 300000 No 0.4.0
impersonation-enable Enable user impersonation for Hive catalog. false No 0.4.0
kerberos.principal The Kerberos principal for the catalog. You should configure gravitino.bypass.hadoop.security.authentication, gravitino.bypass.hive.metastore.kerberos.principal and gravitino.bypass.hive.metastore.sasl.enabledif you want to use Kerberos. (none) required if you use kerberos 0.4.0
kerberos.keytab-uri The uri of key tab for the catalog. Now supported protocols are https, http, ftp, file. (none) required if you use kerberos 0.4.0
kerberos.check-interval-sec The interval to check validness of the principal 60 No 0.4.0
kerberos.keytab-fetch-timeout-sec The timeout to fetch key tab 60 No 0.4.0
list-all-tables Lists all tables in a database, including non-Hive tables, such as Iceberg, etc false No 0.5.1

When you use the Gravitino with Trino. You can pass the Trino Hive connector configuration using prefix trino.bypass.. For example, using trino.bypass.hive.config.resources to pass the hive.config.resources to the Gravitino Hive catalog in Trino runtime.

When you use the Gravitino with Spark. You can pass the Spark Hive connector configuration using prefix spark.bypass.. For example, using spark.bypass.hive.exec.dynamic.partition.mode to pass the hive.exec.dynamic.partition.mode to the Spark Hive connector in Spark runtime.

Catalog operations

Refer to Manage Relational Metadata Using Gravitino for more details.

Schema

Schema capabilities

The Hive catalog supports creating, updating, and deleting databases in the HMS.

Schema properties

Schema properties supply or set metadata for the underlying Hive database. The following table lists predefined schema properties for the Hive database. Additionally, you can define your own key-value pair properties and transmit them to the underlying Hive database.

Property name Description Default value Required Since Version
location The directory for Hive database storage, such as /user/hive/warehouse. HMS uses the value of hive.metastore.warehouse.dir in the hive-site.xml by default. No 0.1.0

Schema operations

see Manage Relational Metadata Using Gravitino.

Table

Table capabilities

  • The Hive catalog supports creating, updating, and deleting tables in the HMS.
  • Doesn't support column default value.

Table partitions

The Hive catalog supports partitioned tables. Users can create partitioned tables in the Hive catalog with the specific partitioning attribute. Although Gravitino supports several partitioning strategies, Apache Hive inherently only supports a single partitioning strategy (partitioned by column). Therefore, the Hive catalog only supports Identity partitioning.

:::caution The fieldName specified in the partitioning attribute must be the name of a column defined in the table. :::

Table sort orders and distributions

The Hive catalog supports bucketed sorted tables. Users can create bucketed sorted tables in the Hive catalog with specific distribution and sortOrders attributes. Although Gravitino supports several distribution strategies, Apache Hive inherently only supports a single distribution strategy (clustered by column). Therefore the Hive catalog only supports Hash distribution.

:::caution The fieldName specified in the distribution and sortOrders attribute must be the name of a column defined in the table. :::

Table column types

The Hive catalog supports all data types defined in the Hive Language Manual. The following table lists the data types mapped from the Hive catalog to Gravitino.

Hive Data Type Gravitino Data Type Since Version
boolean boolean 0.2.0
tinyint byte 0.2.0
smallint short 0.2.0
int/integer integer 0.2.0
bigint long 0.2.0
float float 0.2.0
double/double precision double 0.2.0
decimal decimal 0.2.0
string string 0.2.0
char char 0.2.0
varchar varchar 0.2.0
timestamp timestamp 0.2.0
date date 0.2.0
interval_year_month interval_year 0.2.0
interval_day_time interval_day 0.2.0
binary binary 0.2.0
array array 0.2.0
map map 0.2.0
struct struct 0.2.0
uniontype uniontype 0.2.0

:::info Since 0.6.0, the data types other than listed above are mapped to Gravitino External Type that represents an unresolvable data type from the Hive catalog. :::

Table properties

Table properties supply or set metadata for the underlying Hive tables. The following table lists predefined table properties for a Hive table. Additionally, you can define your own key-value pair properties and transmit them to the underlying Hive database.

Property Name Description Default Value Required Since version
location The location for table storage, such as /user/hive/warehouse/test_table. HMS uses the database location as the parent directory by default. No 0.2.0
table-type Type of the table. Valid values include MANAGED_TABLE and EXTERNAL_TABLE. MANAGED_TABLE No 0.2.0
format The table file format. Valid values include TEXTFILE, SEQUENCEFILE, RCFILE, ORC, PARQUET, AVRO, JSON, CSV, and REGEX. TEXTFILE No 0.2.0
input-format The input format class for the table, such as org.apache.hadoop.hive.ql.io.orc.OrcInputFormat. The property format sets the default value org.apache.hadoop.mapred.TextInputFormat and can change it to a different default. No 0.2.0
output-format The output format class for the table, such as org.apache.hadoop.hive.ql.io.orc.OrcOutputFormat. The property format sets the default value org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat and can change it to a different default. No 0.2.0
serde-lib The serde library class for the table, such as org.apache.hadoop.hive.ql.io.orc.OrcSerde. The property format sets the default value org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe and can change it to a different default. No 0.2.0
serde.parameter. The prefix of the serde parameter, such as "serde.parameter.orc.create.index" = "true", indicating ORC serde lib to create row indexes (none) No 0.2.0

Hive automatically adds and manages some reserved properties. Users aren't allowed to set these properties.

Property Name Description Since Version
comment Used to store a table comment. 0.2.0
numFiles Used to store the number of files in the table. 0.2.0
totalSize Used to store the total size of the table. 0.2.0
EXTERNAL Indicates whether the table is external. 0.2.0
transient_lastDdlTime Used to store the last DDL time of the table. 0.2.0

Table indexes

  • Doesn't support table indexes.

Table operations

Refer to Manage Relational Metadata Using Gravitino for more details.

Alter operations

Gravitino has already defined a unified set of metadata operation interfaces, and almost all Hive Alter operations have corresponding table update requests which enable you to change the struct of an existing table. The following table lists the mapping relationship between Hive Alter operations and Gravitino table update requests.

Alter table
Hive Alter Operation Gravitino Table Update Request Since Version
Rename Table Rename table 0.2.0
Alter Table Properties Set a table property 0.2.0
Alter Table Comment Update comment 0.2.0
Alter SerDe Properties Set a table property 0.2.0
Remove SerDe Properties Remove a table property 0.2.0
Alter Table Storage Properties Unsupported -
Alter Table Skewed or Stored as Directories Unsupported -
Alter Table Constraints Unsupported -

:::note As Gravitino has a separate interface for updating the comment of a table, the Hive catalog sets comment as a reserved property for the table, preventing users from setting the comment property. Apache Hive can modify the comment property of the table. :::

Alter column
Hive Alter Operation Gravitino Table Update Request Since Version
Change Column Name Rename a column 0.2.0
Change Column Type Update the type of a column 0.2.0
Change Column Position Update the position of a column 0.2.0
Change Column Comment Update the column comment 0.2.0
Alter partition

:::note Support for altering partitions is under development. :::