android sqlite 创建空表,sqlite3在android中创建表错误(sqlite3 create table error in android)...
sqlite3在android中创建表错误(sqlite3 create table error in android)
我试图在android中使用sqlite3创建表我的开放助手是这样的：
public class TaskOpenHelper extends BaseOpenHelper {
public static final String TABLE_NAME = "tasks";
public static final String COL_ID = "id";
public static final String COL_USER_ID = "user_id";
public static final String COL_TITLE = "title";
public static final String COL_DATE = "date";
public static final String COL_TIME = "time";
public static final String COL_IS_DONE = "is_done";
public static final String COL_IS_IPM = "is_ipm";
public static final String COL_DESC = "desc";
public static final String COL_REGISTER_TIME = "register_time";
public static final String CREATE_TABLE = "CREATE TABLE IF NOT EXISTS " + TABLE_NAME +
"(" +
COL_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
COL_USER_ID + " INTEGER NOT NULL," +
COL_TITLE + " TEXT NOT NULL," +
COL_DATE + " TEXT ," +
COL_TIME + " TEXT ," +
COL_IS_DONE + " INTEGER ," +
COL_IS_IPM + " INTEGER ," +
COL_DESC + " TEXT," +
COL_REGISTER_TIME + " TEXT," +
"FOREIGN KEY " + COL_USER_ID + " REFERENCES " + UserOpenHelper.TABLE_NAME + "(" + UserOpenHelper.COL_ID + ")" +
");";
public TaskOpenHelper(Context context) {
super(context, DATABASE_NAME, null, VERSION);
}
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL(CREATE_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(sqLiteDatabase);
}
但是当我在尝试创建表时运行app时，这个错误得到了证实：
Caused by: android.database.sqlite.SQLiteException: near "user_id": syntax error (code 1): , while compiling: CREATE TABLE IF NOT EXISTS tasks(id INTEGER PRIMARY KEY AUTOINCREMENT,user_id INTEGER NOT NULL,title TEXT NOT NULL,date TEXT ,time TEXT ,is_done INTEGER ,is_ipm INTEGER ,desc TEXT,register_time TEXT,FOREIGN KEY user_id REFERENCES user(Id));
这个open helper在数据源类中用于执行db的查询
I am trying to create table in android using sqlite3 my open helper is this:
public class TaskOpenHelper extends BaseOpenHelper {
public static final String TABLE_NAME = "tasks";
public static final String COL_ID = "id";
public static final String COL_USER_ID = "user_id";
public static final String COL_TITLE = "title";
public static final String COL_DATE = "date";
public static final String COL_TIME = "time";
public static final String COL_IS_DONE = "is_done";
public static final String COL_IS_IPM = "is_ipm";
public static final String COL_DESC = "desc";
public static final String COL_REGISTER_TIME = "register_time";
public static final String CREATE_TABLE = "CREATE TABLE IF NOT EXISTS " + TABLE_NAME +
"(" +
COL_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
COL_USER_ID + " INTEGER NOT NULL," +
COL_TITLE + " TEXT NOT NULL," +
COL_DATE + " TEXT ," +
COL_TIME + " TEXT ," +
COL_IS_DONE + " INTEGER ," +
COL_IS_IPM + " INTEGER ," +
COL_DESC + " TEXT," +
COL_REGISTER_TIME + " TEXT," +
"FOREIGN KEY " + COL_USER_ID + " REFERENCES " + UserOpenHelper.TABLE_NAME + "(" + UserOpenHelper.COL_ID + ")" +
");";
public TaskOpenHelper(Context context) {
super(context, DATABASE_NAME, null, VERSION);
}
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL(CREATE_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(sqLiteDatabase);
}
but when I run app when trying to create table this error accured:
Caused by: android.database.sqlite.SQLiteException: near "user_id": syntax error (code 1): , while compiling: CREATE TABLE IF NOT EXISTS tasks(id INTEGER PRIMARY KEY AUTOINCREMENT,user_id INTEGER NOT NULL,title TEXT NOT NULL,date TEXT ,time TEXT ,is_done INTEGER ,is_ipm INTEGER ,desc TEXT,register_time TEXT,FOREIGN KEY user_id REFERENCES user(Id));
this open helper is used in a datasource class to executre querys from db
原文：https://stackoverflow.com/questions/32017910
更新时间：2019-06-16 07:52
最满意答案
您需要将user_id放在FOREIGN KEY子句的括号中：
FOREIGN KEY (user_id) REFERENCES user(Id)
整个陈述应该是这样的
CREATE TABLE IF NOT EXISTS tasks(id INTEGER PRIMARY KEY AUTOINCREMENT,
user_id INTEGER NOT NULL,
title TEXT NOT NULL,
date TEXT,
time TEXT,
is_done INTEGER,
is_ipm INTEGER,
desc TEXT,
register_time TEXT,
FOREIGN KEY user_id REFERENCES user(Id));
此外，您必须更改desc列的名称，因为这是SQLite中的保留字 。
You need to put user_id in parentheses in the FOREIGN KEY clause:
FOREIGN KEY (user_id) REFERENCES user(Id)
The entire statement should look like
CREATE TABLE IF NOT EXISTS tasks(id INTEGER PRIMARY KEY AUTOINCREMENT,
user_id INTEGER NOT NULL,
title TEXT NOT NULL,
date TEXT,
time TEXT,
is_done INTEGER,
is_ipm INTEGER,
desc TEXT,
register_time TEXT,
FOREIGN KEY user_id REFERENCES user(Id));
Also you must change the name of the desc column as this is a reserved word in SQLite.
2015-08-14
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