ALTER TABLE Syntax Elements (Datalake Form) - Teradata VantageCloud Lake

Lake - Working with SQL

Deployment
VantageCloud
Edition
Lake
Product
Teradata VantageCloud Lake
Release Number
Published
February 2025
ft:locale
en-US
ft:lastEdition
2025-11-21
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jbe1714339405530.ditamap
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pny1626732985837.ditaval
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jbe1714339405530
column_name
Name of the column, such as first_name, phone_number, and so on.
comment_string
Description string, up to 255 characters.
data_type
The data type of a column, such as BYTE or FLOAT. For all supported data types and limitations, see Open Table Format Data Types.
datalake_name
Name of the Datalake object.
otf_database_name
Name of the database in the Open Table Format (OTF) catalog.
otf_table_name
Name of the OTF table you are modifying. Table must exist.
property_name and property_value
[Optional] Self-defined properties of the table you are creating to write to the Open Table Format metadata.

property_name is an option or credential and property_value is its value.

Do not specify the same name-value pair more than once.

TBLPROPERTIES and PROPERTIES are equivalent.

transform
Transform to apply to the column or columns to produce a partition value.
Transform Column Type Partition Value Partition Value Type
IDENTITY Any Unmodified column Same as column
BUCKET
  • INTEGER
  • BIGINT
  • DECIMAL(precision, scale)
  • DATE
  • TIME(6)
  • TIMESTAMP(6)
  • TIMESTAMP(6) WITH TIME ZONE
  • VARCHAR(32000)
  • VARBYTE(32)
  • BYTE(L) if L <= 64000, otherwise BLOB
  • BLOB
Hash of column value, mod bucket_number INTEGER
TRUNCATE
  • INTEGER
  • BIGINT
  • DECIMAL(precision, scale)
  • VARCHAR(32000)
Column value truncated by width or length. Same as column
YEAR
  • DATE
  • TIMESTAMP(6)
  • TIMESTAMP(6) WITH TIME ZONE
Year extracted from column, as years from 1970 INTEGER
MONTH
  • DATE
  • TIMESTAMP(6)
  • TIMESTAMP(6) WITH TIME ZONE
Month extracted from column, as months from 1970-01-01 INTEGER
DAY
  • DATE
  • TIMESTAMP(6)
  • TIMESTAMP(6) WITH TIME ZONE
Day extracted from column, as days from 1970-01-01 INTEGER
HOUR
  • DATE
  • TIMESTAMP(6)
  • TIMESTAMP(6) WITH TIME ZONE
Hour extracted from column, as days from 1970-01-01 00:00:00 INTEGER
NULL Any NULL INTEGER or same as column