FROM Clause - Teradata Database - Teradata Vantage NewSQL Engine

SQL Data Manipulation Language

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Published
March 2019
Language
English (United States)
Last Update
2019-05-03
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fbo1512081269404.ditamap
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TD_DBS_16_20_Update1.ditaval
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B035-1146
lifecycle
previous
Product Category
Teradata Vantage™
FROM
Keyword introducing a table list of the updated table and any other tables from which field values are taken to update the updated table.
When you use an UPDATE syntax that requires a FROM clause, you should specify the names of all outer tables in the clause.
The UPDATE statement FROM clause is a Teradata extension to the ANSI SQL:2011 standard.
table_name_2
Name of one or more base tables, queue tables, derived tables, or views.
table_name_1 must be a member of the table_name_2 table list.
If you do not specify a correlation name for a table_name_2 list object, or if you define a correlation name for it instead of table_name_1, then table_name_2 cannot be a derived table.
If any table_name_2 list member is a view, then that view must be updatable.
If you do not specify a database name, the system assumes the current database.
correlation_name
Alias for a member of the table_name_2 table list. Correlation names are also referred to as range variables.
A correlation_name must be specified for at least one of the tables in a self-join operation.
If you specify a correlation name for table_name_1 in the table_name_2 table list using the joined tables syntax, you must specify that correlation name instead of the true name for table_name_1. See Example: UPDATE Specifying a Correlation Name for the Updated Table in the FROM Clause.