Help Center/ Data Lake Insight/ SQL Syntax Reference (To Be Offline)/ Spark SQL Syntax Reference (Unavailable Soon)/ Modifying a Table/ Adding a Column
Updated on 2023-11-03 GMT+08:00
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Adding a Column

Function

This statement is used to add one or more new columns to a table.

Syntax

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ALTER TABLE [db_name.]table_name ADD COLUMNS (col_name1 col_type1 [COMMENT col_comment1], ...);

Keyword

  • ADD COLUMNS: columns to add
  • COMMENT: column description

Parameters

Table 1 Parameter description

Parameter

Description

db_name

Database name that contains letters, digits, and underscores (_). It cannot contain only digits or start with an underscore (_).

table_name

Table name

col_name

Column name

col_type

Field type

col_comment

Column description

Precautions

Do not run this SQL statement concurrently. Otherwise, columns may be overwritten.

Example

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ALTER TABLE t1 ADD COLUMNS (column2 int, column3 string);
Parent topic: Modifying a Table