Android房间数据库DAO调试日志

Question

给定如下所示的房间数据库DAO：

import android.arch.persistence.room.Dao;
import android.arch.persistence.room.Query;

import java.util.Date;
import java.util.List;

@Dao
public interface MyDao {

    @Query("SELECT * FROM MyTable")
    List<MyItem> all();

    @Query("SELECT * FROM MyTable WHERE date = :date AND language = :language")
    MyItem byDate(Date date, String language);


}

是否有一种方法可以在mydao中添加一个记录器或类似的东西，这样我就可以看到哪些语句正在执行。这在开发过程中非常有用，因为我可以立即检查函数是否正确地转换为预期的SQL语句。

Answer 1

假设Room使用Framework的Sqlite作为底层数据库，则可以非常简单地记录语句。唯一的限制：这只能在模拟器上完成。

从sqlitedebug.java：

/**
 * Controls the printing of SQL statements as they are executed.
 *
 * Enable using "adb shell setprop log.tag.SQLiteStatements VERBOSE".
 */
public static final boolean DEBUG_SQL_STATEMENTS =
        Log.isLoggable("SQLiteStatements", Log.VERBOSE);  

默认情况下，不设置log.tag.SQLiteStatements的值：

这就是我们必须使用模拟器的原因：

Alex@mbpro:~$adb root
以root身份重新启动adbd
Alex@mbpro:~$adb shell stop
Alex@mbpro:~$adb shell start

模拟器将重新启动。
运行应用程序，您将在logcat中看到类似的Sqlite语句：

<redacted..>
V/SQLiteStatements: <redacted>/my_db: "BEGIN EXCLUSIVE;"
V/SQLiteStatements: <redacted>/my_db: "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)"
V/SQLiteStatements: <redacted>/my_db: "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, "3cb5664b6da264c13388292d98141843")"
V/SQLiteStatements: <redacted>/my_db: "CREATE TABLE IF NOT EXISTS `MyTable` (`id` TEXT NOT NULL, `date` INTEGER, `language` TEXT, PRIMARY KEY(`id`))"
<redacted..>
V/SQLiteStatements: <redacted>/my_db: "BEGIN EXCLUSIVE;"
V/SQLiteStatements: <redacted>/my_db: "PRAGMA temp_store = MEMORY;"
V/SQLiteStatements: <redacted>/my_db: "PRAGMA recursive_triggers='ON';"
V/SQLiteStatements: <redacted>/my_db: "CREATE TEMP TABLE room_table_modification_log(version INTEGER PRIMARY KEY AUTOINCREMENT, table_id INTEGER)"
V/SQLiteStatements: <redacted>/my_db: "COMMIT;"
<redacted..>
V/SQLiteStatements: <redacted>/my_db: "SELECT * FROM MyTable"
V/SQLiteStatements: <redacted>/my_db: "SELECT * FROM MyTable WHERE date = 1551562171387 AND language = 'en'"  

要撤消更改，请使用以下命令：

Alex@mbpro:~$adb shell setprop log.tag.sqlitestatements“
Alex@mbpro:~$adb shell getprop log.tag.sqlitestatements
<--空白行-->
Alex@mbpro:~$adb shell stop
Alex@mbpro:~$adb shell start
Alex@mbpro:~$adb shell start
Alex@mbpro:~$adb unroot
以非root身份重新启动adbd