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Dialect Translation is a feature of SQL Translation Services that enables a Hub or Full-Function Server to route inbound SQL requests to SQL-capable subservers and data adapters wherever possible. Dialect Translation avoids translation to Data Manipulation Language, while maintaining data location transparency.
Dialect Translation transforms an incompatible statement into one that can be processed by the destination SQL engine, while preserving the semantic meaning of the statement.
Dialect Translation is the default behavior of SQL Translation in a Hub or Full-Function Server. This behavior can be modified by changing the server profile or executing a stored procedure to modify the value of the APT variable.
To qualify for Dialect Translation, the request must meet the requirements outlined in Rules for Dialect Translation. If the syntax of a request does not conform to the syntax of the DBMS or is not translatable to the syntax of the DBMS, the request will be translated to DML.
Dialect Translation is shown in the shaded area of the following figure. Valid requests are represented by the broken-line circle as shown in the figure below.
If the incoming request meets the following criteria, Dialect Translation is invoked by SQL Translation Services:
If a request does not meet these requirements but is valid, the server translates the request into Data Manipulation Language using DML Generation. One or more data adapters then generate driver-specific DML and pass it to the DBMS for processing.
The following steps illustrate how a request for relational data is processed using Dialect Translation on a Hub or Full-Function Server:
Incoming SQL syntax is often compatible with the dialect-specific SQL of the target RDBMS. In that case, Dialect Translation substitutes the correct table and column names rather than translates the dialect.
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