Greenplum

Greenplum Table Distribution and Best Practices

Greenplum is a massive parallel processing data store, and data is distributed across segments as per the definition of the distribution strategy. Greenplum Table Distribution uses the two types of distribution, Hash and Random. When you create or alter tables you will have to tell the system which distribution it should use. By default, Greenplum database data distribution uses the hash algorithm. Types of Greenplum Data Distribution Greenplum database distributes data using two methods Column Oriented/Hash Distribution: Distributes data evenly across all segment using the column specified in DISTRIBUTED BY…

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August 22, 2016
Greenplum

Greenplum Sequence and its Usage

Like any other data warehouse appliances, Greenplum has sequences. Greenplum sequence is an auto number generator. These sequence then can be used in any SQL statements. Greenplum Sequence Overview CREATE SEQUENCE creates a new sequence number generator. This command willalso creates the special single-row table and initialize it. Sequence will be owned by the user creating it. Read: Greenplum Data Loading Sequence Also check: Greenplum Unloading Data Syntax: CREATE SEQUENCE name [Options] Following are the options associated with Greenplum sequence. [INCREMENT [BY] value] [MINVALUE minvalue | NO MINVALUE] [MAXVALUE maxvalue…

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August 20, 2016