Your Presto administrator must define a datasource (database connection information) before you can use this block. Presto administrators can also configure Presto to reject insert, update or delete operations for a database. Administrators should see Configure the Default Operations Generated for Database
Mashable for more information. |
Datasource Name | Select the datasource for the database you want to work with. If there is no datasource for this database, contact your Presto administrator to add one. | ||
Enter SQL Statement | Specify the SQL statement for this block. Either: ![]() ![]() ![]()
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Statement Type | If the SQL statement is provided dynamically, from an input parameter or other block, set the appropriate option to indicate whether this statement is a Query statement or an Update statement (for insert, update or delete operations). | ||
Limit the number of records to fetch | Set this option if you want to limit the results from this SQL query or stored procedure to a specific set of rows. This is set by default to fetch the first 20 rows in Wires. This is a good practice in general to help ensure good performance for the mashup. | ||
Fetch records starting at row number | If you have chosen to limit the records to fetch, select or enter the number of the first record to return. Or click ![]() | ||
Maximum number of records to fetch | If you have chosen to limit the records to fetch, select or enter the total number of rows to return. Or click ![]() | ||
Fetch size to use with database connection | Select or enter the number of records that this mashup should request from this datasource at one time. Or click ![]() Setting a fetch size is generally a good idea when the dataset for this query may be large. It helps to optimize how the mashup retrieves the results, both to improve performance and ensure adequate memory for the query. For more information, see the <sql> topic. |