// Reason why cannot lock conn.PrepareContext
	// suppose the maxopen is 1, g1 is creating record and g2 is querying record.
	// 1. g1 begin tx, g1 is requeue because of waiting for the system call, now `db.ConnPool` db.numOpen == 1.
	// 2. g2 select lock `conn.PrepareContext(ctx, query)`, now db.numOpen == db.maxOpen , wait for release.
	// 3. g1 tx exec insert, wait for unlock `conn.PrepareContext(ctx, query)` to finish tx and release.

	"gorm.io/gorm"
	. "gorm.io/gorm/utils/tests"
)

type wrapperTx struct {
	*sql.Tx
	conn *wrapperConnPool
}

func (c *wrapperTx) PrepareContext(ctx context.Context, query string) (*sql.Stmt, error) {
	c.conn.got = append(c.conn.got, query)
	return c.Tx.PrepareContext(ctx, query)
}

func (c *wrapperTx) ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error) {

}

type ParamsFilter interface {
	ParamsFilter(ctx context.Context, sql string, params ...interface{}) (string, []interface{})
}

// ConnPool db conns pool interface
type ConnPool interface {
	PrepareContext(ctx context.Context, query string) (*sql.Stmt, error)
	ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error)
	QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)

pkg database/sql/driver, type ConnBeginTx interface, BeginTx(context.Context, TxOptions) (Tx, error)
pkg database/sql/driver, type ConnPrepareContext interface { PrepareContext }
pkg database/sql/driver, type ConnPrepareContext interface, PrepareContext(context.Context, string) (Stmt, error)
pkg database/sql/driver, type ExecerContext interface { ExecContext }

pkg database/sql, method (*Conn) ExecContext(context.Context, string, ...interface{}) (Result, error)
pkg database/sql, method (*Conn) PingContext(context.Context) error
pkg database/sql, method (*Conn) PrepareContext(context.Context, string) (*Stmt, error)
pkg database/sql, method (*Conn) QueryContext(context.Context, string, ...interface{}) (*Rows, error)