The SELECT...WHERE statement interface

The following figure shows the order in which the database server executes purpose functions for a SELECT statement with a WHERE clause.
Figure 1. Processing a SELECT statement scan
This flowchart shows am_scancost pointing to am_open, which points to am_beginscan, which points to am_getnext, which either returns MI_ROWS and re-executes, or returns MI_NO_MORE_RESULTS.
Parent topic: Purpose-function flow
Related reference:
Process queries that involve a virtual table
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