diff --git a/.gitignore b/.gitignore
index 70681cbc..0f1d00e1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,3 @@
 *.test
 *~
 *.swp
-.idea
diff --git a/conn.go b/conn.go
index 421e096a..55152b12 100644
--- a/conn.go
+++ b/conn.go
@@ -1245,10 +1245,6 @@ func (st *stmt) Close() (err error) {
 }
 
 func (st *stmt) Query(v []driver.Value) (r driver.Rows, err error) {
-	return st.query(v)
-}
-
-func (st *stmt) query(v []driver.Value) (r *rows, err error) {
 	if st.cn.bad {
 		return nil, driver.ErrBadConn
 	}
diff --git a/conn_go18.go b/conn_go18.go
index 732eaf67..0fdd06a6 100644
--- a/conn_go18.go
+++ b/conn_go18.go
@@ -42,14 +42,6 @@ func (cn *conn) ExecContext(ctx context.Context, query string, args []driver.Nam
 	return cn.Exec(query, list)
 }
 
-// Implement the "ConnPrepareContext" interface
-func (cn *conn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
-	if finish := cn.watchCancel(ctx); finish != nil {
-		defer finish()
-	}
-	return cn.Prepare(query)
-}
-
 // Implement the "ConnBeginTx" interface
 func (cn *conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
 	var mode string
@@ -155,60 +147,3 @@ func (cn *conn) cancel(ctx context.Context) error {
 		return err
 	}
 }
-
-// Implement the "StmtQueryContext" interface
-func (st *stmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
-	list := make([]driver.Value, len(args))
-	for i, nv := range args {
-		list[i] = nv.Value
-	}
-	finish := st.watchCancel(ctx)
-	r, err := st.query(list)
-	if err != nil {
-		if finish != nil {
-			finish()
-		}
-		return nil, err
-	}
-	r.finish = finish
-	return r, nil
-}
-
-// Implement the "StmtExecContext" interface
-func (st *stmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
-	list := make([]driver.Value, len(args))
-	for i, nv := range args {
-		list[i] = nv.Value
-	}
-
-	if finish := st.watchCancel(ctx); finish != nil {
-		defer finish()
-	}
-
-	return st.Exec(list)
-}
-
-func (st *stmt) watchCancel(ctx context.Context) func() {
-	if done := ctx.Done(); done != nil {
-		finished := make(chan struct{})
-		go func() {
-			select {
-			case <-done:
-				_ = st.cancel()
-				finished <- struct{}{}
-			case <-finished:
-			}
-		}()
-		return func() {
-			select {
-			case <-finished:
-			case finished <- struct{}{}:
-			}
-		}
-	}
-	return nil
-}
-
-func (st *stmt) cancel() error {
-	return st.cn.cancel()
-}