explain
Returns a string describing the implementation of the compiled query. This is intended to be read by a developer for purposes of optimizing the query, especially to add database indexes. It's not machine-readable and its format may change. As currently implemented, the result is two or more lines separated by newline characters:
The first line is the SQLite SELECT statement.
The subsequent lines are the output of SQLite's "EXPLAIN QUERY PLAN" command applied to that statement.
For help interpreting this, see: eqp. The most important thing to know is that if you see "SCAN TABLE", it means that SQLite is doing a slow linear scan of the documents instead of using an index.
Return
a string describing the implementation of the compiled query.
Throws
if an error occurs