如何使AUTO_INCREMENT在Android SQLite数据库？ [英] How to make AUTO_INCREMENT on Android SQLite database?

问题描述

嘿，我想创建一个AUTO_INCREMENT列的数据库。但我不知道如何分析的方法插入值。我只是不知道该怎么解析到一个AUTO_INCREMENT说法，而我解析1，其中应AUTO_INCREMENT，但我知道它不是我应该解析。

下面是 CallDatHelper.java 类，我宣布方法插入和创建数据库的方法。

 包com.psyhclo;

进口android.content.Context;
进口android.database.Cursor;
进口android.database.sqlite.SQLiteDatabase;
进口android.database.sqlite.SQLiteOpenHelper;
进口android.database.sqlite.SQLiteStatement;
进口android.util.Log;

进口的java.util.ArrayList;
进口的java.util.List;

公共类CallDataHelper {

私有静态最后弦乐DATABASE_NAME =calls.db;
私有静态最终诠释DATABASE_VERSION = 1;
私有静态最后弦乐TABLE_NAME =contact_data;

私人上下文的背景下;
私人SQLiteDatabase分贝;

公共CallDataHelper（上下文的背景下）{
    this.context =背景;
    OpenHelper openHelper =新OpenHelper（this.context）;
    this.db = openHelper.getWritableDatabase（）;
}

公共布尔插入（CID整数，字符串CNAME，字符串numType，
        字符串CNUM，字符串DUR，字符串日期，字符串currTime）{
    this.db.execSQL（插入
            + TABLE_NAME
            +（同上，CONTACT_ID，CONTACT_NAME，NUMBER_TYPE，contact_number，时间，日期，CURRENT_TIME，续）
            +的值（？，+ CID +，+ CNAME +，+ numType +，
            + CNUM +，+ DUR +，+日期+，+ currTime +，）？）;
    返回true;
}

公共无效atualiza（串词）{
    this.db.execSQL（更新字数设置续=续+ 1 WHERE（字=？），
            新的String [] {文字}）;
}

公共无效用deleteAll（）{
    this.db.delete（TABLE_NAME，NULL，NULL）;
}

公共布尔选择（字符串WRD）{

    串词;
    光标光标= this.db.query（TABLE_NAME，新的String [] {字}，
            字怎​​么样？，新的String [] {} WRD，NULL，NULL，NULL）;
    如果（cursor.moveToFirst（））{
        做 {
            字= cursor.getString（0）;
        }而（cursor.moveToNext（））;
    }
    如果（光标=空＆安培;！＆安培;！cursor.isClosed（））{
        cursor.close（）;
        返回true;
    } 其他 {
        返回false;
    }
}

公开名单＆LT;字符串＆GT;全选（） {
    名单＆LT;字符串＆GT;名单=新的ArrayList＆LT;字符串＆GT;（）;
    光标光标= this.db.query（TABLE_NAME，新的String [] {字}，
            NULL，NULL，NULL，NULL，续递减）;
    如果（cursor.moveToFirst（））{
        做 {
            list.add（cursor.getString（0）.toUpperCase（））;
        }而（cursor.moveToNext（））;
    }
    如果（光标=空＆安培;！＆安培;！cursor.isClosed（））{
        cursor.close（）;
    }
    返回列表;
}

私有静态类OpenHelper扩展SQLiteOpenHelper {

    OpenHelper（上下文的背景下）{
        超（背景下，DATABASE_NAME，空，DATABASE_VERSION）;
    }

    @覆盖
    公共无效的onCreate（SQLiteDatabase DB）{
        db.execSQL（CREATE TABLE
                + TABLE_NAME
                +（ID INTEGER PRIMARY KEY AUTOINCREMENT，CONTACT_ID INTEGER，CONTACT_NAME VARCHAR（50），NUMBER_TYPE VARCHAR（50），contact_number VARCHAR（50），持续时间，日期DATE，TIME CURRENT_TIME，续INTEGER））;

    }

    @覆盖
    公共无效onUpgrade（SQLiteDatabase分贝，INT oldVersion，诠释静态网页）{
        Log.w（RatedCalls数据库，
                升级数据库，这将删除表并重新创建。）;
        db.execSQL（DROP TABLE IF EXISTS+ TABLE_NAME）;
        的onCreate（DB）;
    }
}
}
 

和这里就是我称之为插入方式解析我想插入的数据。

  this.dh.insert（1，1，联系人姓名，numType，contactNumber，
                    期间，callDate，currTime）;
 

解决方案

您不必解析什么。如果列创建为 AUTOINCREMENT ，只是通过其他值：

  db.execSQL（插入
        + TABLE_NAME
        +（CONTACT_ID，CONTACT_NAME，NUMBER_TYPE，contact_number，时间，日期，CURRENT_TIME，续）
        +的值（+ CID +，+ CNAME +，+ numType +，
        + CNUM +，+ DUR +，+日期+，+ currTime +，）？）;
 

顺便说一句，它总是建议插入使用Android的数据插入方法：

  ContentValues​​值=新ContentValues​​（）;
values​​.put（CONTACT_ID，CID）;
values​​.put（CONTACT_NAME，CNAME）;
// 等等。
db.insert（TABLE_NAME，空，价值观）;
 

Hey I want to create a database with an AUTO_INCREMENT column. But I don't know how to parse the value in the method insert. I just don't know what to parse to an AUTO_INCREMENT argument, and I parsed 1 where should be auto_increment, but I know its not that I should parse.

Here is the CallDatHelper.java class where I declare the method insert, and the method that creates the database.

package com.psyhclo;

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteStatement;
import android.util.Log;

import java.util.ArrayList;
import java.util.List;

public class CallDataHelper {

private static final String DATABASE_NAME = "calls.db";
private static final int DATABASE_VERSION = 1;
private static final String TABLE_NAME = "contact_data";

private Context context;
private SQLiteDatabase db;

public CallDataHelper(Context context) {
    this.context = context;
    OpenHelper openHelper = new OpenHelper(this.context);
    this.db = openHelper.getWritableDatabase();
}

public boolean insert(Integer cId, String cName, String numType,
        String cNum, String dur, String date, String currTime) {
    this.db.execSQL("insert into "
            + TABLE_NAME
            + "(id, contact_id, contact_name, number_type, contact_number, duration, date, current_time, cont) "
            + "values( ? ," + cId + ", " + cName + ", " + numType + ", "
            + cNum + ", " + dur + ", " + date + ", " + currTime + ", ? )");
    return true;        
}

public void atualiza(String word) {
    this.db.execSQL("UPDATE words SET cont = cont + 1 WHERE (word= ?)",
            new String[] { word });
}

public void deleteAll() {
    this.db.delete(TABLE_NAME, null, null);
}

public boolean select(String wrd) {

    String word;
    Cursor cursor = this.db.query(TABLE_NAME, new String[] { "word" },
            "word like ?", new String[] { wrd }, null, null, null);
    if (cursor.moveToFirst()) {
        do {
            word = cursor.getString(0);
        } while (cursor.moveToNext());
    }
    if (cursor != null && !cursor.isClosed()) {
        cursor.close();
        return true;
    } else {
        return false;
    }
}

public List<String> selectAll() {
    List<String> list = new ArrayList<String>();
    Cursor cursor = this.db.query(TABLE_NAME, new String[] { "word" },
            null, null, null, null, "cont desc");
    if (cursor.moveToFirst()) {
        do {
            list.add(cursor.getString(0).toUpperCase());
        } while (cursor.moveToNext());
    }
    if (cursor != null && !cursor.isClosed()) {
        cursor.close();
    }
    return list;
}

private static class OpenHelper extends SQLiteOpenHelper {

    OpenHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE "
                + TABLE_NAME
                + "(id INTEGER PRIMARY KEY AUTOINCREMENT, contact_id INTEGER, contact_name VARCHAR(50), number_type VARCHAR(50), contact_number VARCHAR(50), duration TIME, date DATE, current_time TIME, cont INTEGER)");

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.w("RatedCalls Database",
                "Upgrading database, this will drop tables and recreate.");
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        onCreate(db);
    }
}
}

And here is where I call the insert method parsing the data I want to insert.

this.dh.insert(1 , 1, contactName, numType, contactNumber,
                    duration, callDate, currTime);

解决方案

You don't have to parse anything. If the column was created as AUTOINCREMENT, just pass the other values:

db.execSQL("insert into "
        + TABLE_NAME
        + "(contact_id, contact_name, number_type, contact_number, duration, date, current_time, cont) "
        + "values( "+ cId + ", " + cName + ", " + numType + ", "
        + cNum + ", " + dur + ", " + date + ", " + currTime + ", ? )");

By the way, it's always recommended to insert data using the Android's insert method:

ContentValues values = new ContentValues();
values.put("contact_id", cId);
values.put("contact_name", cName);
// etc.
db.insert(TABLE_NAME, null, values);

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