创建唯一复合列的语法 - Android SQLiteOpenHelper

Question

我的 SQLiteOpenHelper 中有这个 onCreate 方法 class，我想在这两列（复合唯一列）上添加一个唯一约束：

SongContract.SongEntry.COLUMN_TITLE
SongContract.SongEntry.COLUMN_RELEASEDATE

但是我得到一个错误：

Cannot resolve method UNIQUE

这是我的代码：

public void onCreate(SQLiteDatabase db) {
    final String SQL_CREATE_SONG_TABLE = "CREATE TABLE " + SongContract.SongEntry.TABLE_SONG + " (" +
        SongContract.SongEntry._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
        SongContract.SongEntry.COLUMN_TITLE + " TEXT NOT NULL, " +
        SongContract.SongEntry.COLUMN_RELEASEDATE + " INTEGER, " +
        UNIQUE(SongContract.SongEntry.COLUMN_TITLE, SongContract.SongEntry.COLUMN_RELEASEDATE) +
        SongContract.SongEntry.COLUMN_RATING + " TEXT);";

    db.execSQL(SQL_CREATE_SONG_TABLE);
}

实现我的目标的正确语法是什么？

Answer 1

我在尝试了 sqllite 之后找到了正确的语法：

最终字符串 SQL_CREATE_SONG_TABLE = "CREATE TABLE " + SongContract.SongEntry.TABLE_SONG + " (" + SongContract.SongEntry._ID + "整数主键自增，" + SongContract.SongEntry.COLUMN_TITLE + "文本不为空，" + SongContract.SongEntry.COLUMN_RELEASEDATE + "整数不为空，" + SongContract.SongEntry.COLUMN_RATING + " TEXT, " + "UNIQUE" + "(" + SongContract.SongEntry.COLUMN_TITLE + "," + SongContract.SongEntry.COLUMN_RELEASEDATE + ") " + ");";

创建唯一复合列的语法 - Android SQLiteOpenHelper

Syntax to create unique composite column - Android SQLiteOpenHelper

java

android

sqlite

sqliteopenhelper