USING ( using_spec [,...] ) SQL_request
Syntax Elements
- using_spec
using_variable_name data_type [ data_type_attribute [...] ]
[ AS { DEFERRED [BY NAME] | LOCATOR } ]
- SQL_request
- The SQL request with which the USING request modifier is associated.
- This can be a multistatement request, any non-DDL single-statement request, or an explicit transaction.
- You can pass the value for n in a TOP n operator in an SQL request by specifying a USING-defined parameter. See Example: USING Request Modifier with TOP Operator.
- All USING variable names in the SQL request must be preceded by a COLON character.
- using_variable_name
- Name of a USING variable that is to be referenced as a parameter in the SQL request associated with the modifier.
- Each name specified must be unique.
- During processing, each using_variable_name in the SQL request is replaced by a constant value read from the client application.
- You can also use dot notation to access DATASET and JSON data. See Teradata Vantage™ - DATASET Data Type, B035-1198 and Teradata Vantage™ - JSON Data Type, B035-1150.
- data_type
- Data type of the constant value substituted for using_variable_name.
- UDT types are not supported directly. See USING Support for UDTs for details and information about conversion workarounds.
- This can be used to set a default value.
- See Teradata Vantage™ - Data Types and Literals, B035-1143 for a list of data types.
- data_type_attribute
- One of the following data type attributes.
- The only data type attributes that affect the handling of values imported by USING are the following:
- CASESPECIFIC
- NOT CASESPECIFIC
- UPPERCASE
- The server character set attribute (for example CHARACTER SET LATIN) cannot be part of data_type_attribute.
- Type attributes are Teradata extensions to the ANSI SQL:2011 standard.
- DEFERRED
- LOB data is sent to Vantage from the client application when requested, and separately from other row data.
- This option is only valid for LOB data.
- See USING Support for Large Objects for more information.
- BY NAME
- Interpret the data in the USING row as a client file name. When the system detects the BY NAME option following AS DEFERRED, the following events occur in the order indicated:
- The database sends the file name back to the client.
- The client opens the file.
- The client sends the data in the file to the database.
- LOCATOR
- The client application passes a locator for the LOB, generated from a previous SELECT request for the session, to the database.
- This option is only valid for LOB data.
- See USING Support for Large Objects for more information.