Argument Types and Rules - Advanced SQL Engine - Teradata Database

SQL Functions, Expressions, and Predicates

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Published
July 2021
Language
English (United States)
Last Update
2021-07-28
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SQL_Functions__Expressions__and_Predicates.Upload_071421/djk1612415574830.ditamap
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SQL_Functions__Expressions__and_Predicates.Upload_071421/wrg1590696035526.ditaval
dita:id
B035-1145
lifecycle
previous
Product Category
Teradata Vantageā„¢

Expressions passed to this function must have the following data types:

  • inkey = NUMERIC, VARCHAR
  • source_string = CHAR, VARCHAR
  • regexp_string = CHAR, VARCHAR
  • match_arg = VARCHAR

The function returns an error if this size is exceeded or if match_arg = 'l' is specified.

If the inkey is null, an empty string is returned.

The x match option ignores whitespace characters in the pattern/regexp_string. By default, whitespace characters match themselves.

If Vantage passes constants as the second and third parameter in an OREPLACE call, the character type of the first argument is passed as Unicode, and calls oreplace_unicode() with the return type VARCHAR in Unicode charset.

You can also pass arguments with data types that can be converted to the above types using the implicit data type conversion rules that apply to UDFs.

The UDF implicit type conversion rules are more restrictive than the implicit type conversion rules normally used by Vantage. If an argument cannot be converted to the required data type following the UDF implicit conversion rules, it must be explicitly cast.