# tCombinedSQLAggregate Provides a set of matrix based on values or calculations. tCombinedSQLAggregate collects data values from one or more columns of a table for statistical purposes. This component has real-time capabilities since it runs the data transformation on the DBMS itself. ## tCombinedSQLAggregate Standard properties These properties are used to configure tCombinedSQLAggregate running in the Standard Job framework. The Standard tCombinedSQLAggregate component belongs to the ELT family. The component in this framework is available in all Talend products. ## Basic settings | Properties | Description | | --- | --- | | Schema and Edit
schema |

A schema is a row description, it defines the number of fields that will be processed and passed on to the next component. The schema is either built-in or remote in the Repository.

Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available:
- View schema: choose this option to view the schema only.
- Change to built-in property: choose this option to change the schema to Built-in for local changes.
- Update repository connection: choose this option to change the schema stored in the repository and decide whether to propagate the changes to all the Jobs upon completion.
  
  If you just want to propagate the changes to the current Job, you can select No upon completion and choose this schema metadata again in the Repository Content window.
Click Sync columns to retrieve the schema from the previous component connected in the Job.
Built-in: You create and store the schema locally for this component only. For more information about a component schema in its Basic settings tab, see Basic settings tab.
Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Jobs. For more information about a component schema in its Basic settings tab, see Basic settings tab.

| | Group by |

Define the aggregation sets, the values of which will be used for calculations.
Output Column: Select the column label in the list offered according to the schema structure you defined. You can add as many output columns as you wish to make more precise aggregations.
Input Column: Select the input column label to match the output column's expected content, in case the output label of the aggregation set needs to be different.

| | Operations |

Select the type of operation along with the value to use for the calculation and the output field.
Output Column: Select the destination field in the list.
Function: Select any of the following operations to perform on data: count, min, max, avg, sum, first, last, distinct and count (distinct).
Input column: Select the input column from which you want to collect the values to be aggregated.

| ## Advanced settings | Properties | Description | | --- | --- | | tStatCatcher Statistics | Select this check box to gather the Job processing metadata at a
Job level as well as at each component level. | ## Global Variables | Variables | Description | | --- | --- | | Global Variables | NB\_LINE: the number of rows read by an input component
or transferred to an output component. This is a Flow variable and it returns an
integer.

QUERY: the query statement
being processed. This is a Flow variable and it returns a string.

ERROR\_MESSAGE: the error message generated by the
component when an error occurs. This is an After variable and it returns a string. This
variable functions only if the Die on error checkbox is
cleared, if the component has this checkbox.

A Flow variable functions during the execution of a component
while an After variable functions after the execution of the component.

To fill up a field or expression with a variable, press Ctrl+Space to access the variable list and choose the variable to use from
it.

For more information about variables, see [Using contexts and variables](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/contexts-and-variables). | ## Usage | Usage guidance | Description | | --- | --- | | **Usage rule** | This component is an intermediary component. The use of the
corresponding connection and commit components is recommended when
using this component to allow a unique connection to be open and
then closed during the Job execution. | **Related concepts** * [Filtering and aggregating table columns directly on the DBMS](https://help.qlik.com/talend/en-US/components/8.0/combinedsql/tcombinedsqlinput-tcombinedsqlfilter-tmysqlinput-filtering-and-aggregating-table-columns-directly-on-dbms-standard-component-the)