Access to sqlite3_db_cacheflush via Connection

Fix #984

src/inner_connection.rs

@@ -302,6 +302,12 @@ impl InnerConnection {
         false
     }
 
+    #[cfg(feature = "modern_sqlite")] // 3.10.0
+    pub fn cache_flush(&mut self) -> Result<()> {
+        check!(unsafe { ffi::sqlite3_db_cacheflush(self.db()) });
+        Ok(())
+    }
+
     #[cfg(not(feature = "hooks"))]
     #[inline]
     fn remove_hooks(&mut self) {}

src/lib.rs

@@ -868,6 +868,13 @@ impl Connection {
     pub fn is_busy(&self) -> bool {
         self.db.borrow().is_busy()
     }
+
+    /// Flush caches to disk mid-transaction
+    #[cfg(feature = "modern_sqlite")] // 3.10.0
+    #[cfg_attr(docsrs, doc(cfg(feature = "modern_sqlite")))]
+    pub fn cache_flush(&self) -> Result<()> {
+        self.db.borrow_mut().cache_flush()
+    }
 }
 
 impl fmt::Debug for Connection {