[teiid-issues] [JBoss JIRA] Resolved: (TEIID-1653) Support Cursoring over ODBC protocol ( support UseDeclareFetch = 1)

Support Cursoring over ODBC protocol ( support UseDeclareFetch = 1) ------------------------------------------------------------------- Key: TEIID-1653 URL: https://issues.jboss.org/browse/TEIID-1653 Project: Teiid Issue Type: Feature Request Components: ODBC Affects Versions: 7.1.1 Reporter: Ramesh Reddy Assignee: Ramesh Reddy Fix For: 7.4.1, 7.5, 7.1.1 Postgres ODBC driver, retrieves all the rows from server for "select" request before it passes a single row to the calling client. This requires additional memory overhead for the client applications that dealing with very large resultset, which can lead to OOM issues. Postgres ODBC driver supports a couple properties UseDeclareFetch = 1 Fetch=1000 using which, ODBC driver will form the queries using postgres "cursor" functionality, and only fetch number of rows that are defined with variable "Fetch". This will result in faster initial response time to the user (especially UI based apps) because the driver is not fetching all rows, it is only fetching the first batch. Also, minimal memory foot print as it can clear the results as they are delivered to the client application, especially with FORWARD only cursor. Teiid will only support for FORWARD ONLY cursor.