(21) API 使用 NULL 准备语句调用

Question

I am currently working with sqlite database, android. I want to import raw file which contains sql statements into my database. My scenario as follows.

将原始文件读取为字符串
用 ; 符号拆分那些 sql 语句
在循环中执行每个语句

但是当我执行 sql 语句时它会抛出 (21) API called with NULL prepared statement 和 (21) misuse at line 70084 of [b3bb660af9] 等错误仅执行文件的一行之后。我看不出我的编码有任何问题。

错误日志

03-08 14:56:41.652 15867-15867/com.sv.gauge D/EXECUTED SQL: PRAGMA foreign_keys=OFF
03-08 14:56:41.662 15867-15867/com.sv.gauge E/SQLiteLog: (21) API called with NULL prepared statement
03-08 14:56:41.662 15867-15867/com.sv.gauge E/SQLiteLog: (21) misuse at line 70084 of [b3bb660af9]
03-08 14:56:41.672 15867-15867/com.sv.gauge D/AndroidRuntime: Shutting down VM
03-08 14:56:41.672 15867-15867/com.sv.gauge E/AndroidRuntime: FATAL EXCEPTION: main
                                                          Process: com.sv.gauge, PID: 15867
                                                          java.lang.RuntimeException: Unable to start activity ComponentInfo{com.sv.gauge/com.sv.gauge.LoginActivity}: android.database.sqlite.SQLiteException: not an error (code 0)
                                                          #################################################################
                                                          Error Code : 0 (SQLITE_OK)
                                                          Caused By : not an error (code 0)
                                                          #################################################################
                                                              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2695)
                                                              at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2769)
                                                              at android.app.ActivityThread.access0(ActivityThread.java:177)
                                                              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1430)
                                                              at android.os.Handler.dispatchMessage(Handler.java:102)
                                                              at android.os.Looper.loop(Looper.java:135)
                                                              at android.app.ActivityThread.main(ActivityThread.java:5910)
                                                              at java.lang.reflect.Method.invoke(Native Method)
                                                              at java.lang.reflect.Method.invoke(Method.java:372)
                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1405)
                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1200)
                                                           Caused by: android.database.sqlite.SQLiteException: not an error (code 0)
                                                          #################################################################
                                                          Error Code : 0 (SQLITE_OK)
                                                          Caused By : not an error (code 0)
                                                          #################################################################
                                                              at android.database.sqlite.SQLiteConnection.nativeExecuteForChangedRowCount(Native Method)
                                                              at android.database.sqlite.SQLiteConnection.executeForChangedRowCount(SQLiteConnection.java:904)
                                                              at android.database.sqlite.SQLiteSession.executeForChangedRowCount(SQLiteSession.java:754)
                                                              at android.database.sqlite.SQLiteStatement.executeUpdateDelete(SQLiteStatement.java:64)
                                                              at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1814)
                                                              at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1743)
                                                              at com.sv.gauge.controller.GaugeDatabaseHelper.onCreate(GaugeDatabaseHelper.java:78)
                                                              at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:251)
                                                              at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:187)
                                                              at com.sv.gauge.controller.GaugeDatabaseHelper.getReadableDatabase(GaugeDatabaseHelper.java:43)
                                                              at com.sv.gauge.controller.GaugeDatabaseHelper.<init>(GaugeDatabaseHelper.java:37)
                                                              at com.sv.gauge.LoginActivity.onCreate(LoginActivity.java:39)
                                                              at android.app.Activity.performCreate(Activity.java:6178)
                                                              at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
                                                              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2648)
                                                                ... 10 more

用于导入原始 sql 文件的代码片段

@Override
public void onCreate(SQLiteDatabase db) {
    InputStream inputStream = context.getResources().openRawResource(R.raw.database);
    BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
    String line;

    StringBuilder builder = new StringBuilder();
    try {
        while ((line = reader.readLine()) != null) {
            builder.append(line);
            builder.append(System.getProperty("line.separator"));
        }
        String rawSql = builder.toString();

        String[] sqls = rawSql.split(";");
        for (String sql : sqls) {
            db.execSQL(sql);
            Log.d("EXECUTED SQL", sql);
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
}

包含 sql 语句的原始文件

PRAGMA foreign_keys=OFF;
BEGIN TRANSACTION;
CREATE TABLE "domain" (
    `id`    INTEGER PRIMARY KEY AUTOINCREMENT,
    `title` TEXT NOT NULL,
    `description`   TEXT NOT NULL,
    `first_step`    INTEGER NOT NULL
);
INSERT INTO "domain" VALUES(1,'GENERATOR ROOM','take measurements of generator room',1);
CREATE TABLE "domain_step" (
    `id`    INTEGER PRIMARY KEY AUTOINCREMENT,
    `domain_id` INTEGER NOT NULL,
    `title` TEXT NOT NULL,
    `visual_type`   TEXT NOT NULL,
    `visual_link`   TEXT,
    `visual_description`    TEXT NOT NULL,
    `next_step` INTEGER,
    `show_map`  INTEGER NOT NULL,
    `last_step` INTEGER NOT NULL,
    `map_from_previous_link`    TEXT,
    `enable_skip`   INTEGER NOT NULL,
    `skip_to_step`  INTEGER,
    `map_from_beginning_link`   TEXT,
    `value_type`    TEXT NOT NULL,
    `value_hint`    TEXT,
    `default_value` TEXT,
    `default_from_value`    TEXT,
    `default_to_value`  TEXT,
    `report_description`    TEXT
);
INSERT INTO "domain_step" VALUES(1,1,'Safty Items','IMAGE',NULL,'Did you ware safety Items?

1) Ear protection

2) Helmet with light',2,0,0,NULL,0,NULL,NULL,'NONE',NULL,NULL,NULL,NULL,NULL);
COMMIT;

Answer 1

如果 sql 文件已经有“;”然后

try {
    while ((line = reader.readLine()) != null) {
        builder.append(line);
        builder.append(System.getProperty("line.separator"));
    }

应该是

try {
    while ((line = reader.readLine()) != null) {
        builder.append(line);
    }

Answer 2

其他访客的另一个选择

我收到此行是因为我的 SQL 脚本中有一条以 ; 字符结尾的注释。因此，它试图自己只执行注释，从而产生 "NULL prepared statement" 错误。

-- version 1 of the database vocab table was
--
-- CREATE TABLE vocab
-- ( _id INTEGER PRIMARY KEY,
--   date INTEGER,
--   list_id TEXT NOT NULL, -- this should have been INTEGER
--   mongol TEXT NOT NULL,
--   definition TEXT,
--   pronunciation TEXT,
--   audio TEXT,
--   FOREIGN KEY(list_id) REFERENCES lists(_id)
-- );

PRAGMA foreign_keys=off;

BEGIN TRANSACTION;

ALTER TABLE vocab RENAME TO _vocab_old;

...

解决方案

您可以通过执行以下任一操作来解决此问题：

删除以 ;

在 ; 之后添加额外的文字。我这样做了：

-- version 1 of the database vocab table was
--
-- CREATE TABLE vocab
-- ( _id INTEGER PRIMARY KEY,
--   date INTEGER,
--   list_id TEXT NOT NULL, -- this should have been INTEGER
--   mongol TEXT NOT NULL,
--   definition TEXT,
--   pronunciation TEXT,
--   audio TEXT,
--   FOREIGN KEY(list_id) REFERENCES lists(_id)
-- ); -- end comment (comment lines cannot end with semicolon)

更改运行脚本的逻辑，使其忽略任何以 -- 开头的行，并且不会尝试运行它们。

结论

如果您收到此错误，请查找可能单独执行的 ; 个杂散字符。

(21) API 使用 NULL 准备语句调用

(21) API called with NULL prepared statement

database

sqlite

android

batch-processing

android-sqlite