SQL is a standardized query language used to access and manage information in databases. Its scope includes data query and update, schema creation and modification, and data access control. Talend Studio provides a range of SQL templates to simplify the most common tasks. It also comprises a SQL editor which allows you to customize or design your own SQL templates to meet less common requirements.
These SQL templates are used with the components from the Talend ELT component family including tSQLTemplate, tSQLTemplateFilterColumns, tSQLTemplateCommit, tSQLTemplateFilterRows, tSQLTemplateRollback, tSQLTemplateAggregate and tSQLTemplateMerge. These components execute the selected SQL statements. Using the UNION, EXCEPT and INTERSECT operators, you can modify data directly on the DBMS without using the system memory.
Moreover, with the help of these SQL templates, you can optimize the efficiency of your database management system by storing and retrieving your data according to the structural requirements.
Talend Studio provides the following types of SQL templates under the SQL templates node in the Repository tree view:
System SQL templates: They are classified according to the type of database for which they are tailored.
User-defined SQL templates: these are templates which you have created or adapted from existing templates.
More detailed information about the SQL templates is presented in the below sections.
As most of the SQL templates are tailored for specific databases, if you change database in your system, it is inevitable to switch to or develop new templates for the new database.