CFITSIO Table Row Selection

In many of ISDC tools, you have a possibility to apply a selection string to choose only data relevant for your task. Row selection allows applications to build an algebraic expression that evaluates to TRUE or FALSE for each row of a table element, or set of table elements. If the expression is TRUE for a given row, then that row is selected (the result of selection is API function specific), otherwise it is not selected. The expression can be an arbitrarily complex series of operations performed on constants, attribute values, and table columns for a given table element. Below we describe the details of the row selection syntax, this part was mostly taken from the Data Access Layer Users Guide, which you may find in $ISDC_ENV/help/dal.ps.