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SQLite增删改查的基本使用语法

SQLite增删改查的基本使用语法:

打印的log如下:

package com.example.sqlitedemo;

import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        SQLiteDatabase db = openOrCreateDatabase("stu.db",MODE_PRIVATE,null);
        db.execSQL("create table if not exists stutb(_id integer primary key autoincrement,name text not null,sex text not null,age integer not null)");

        ContentValues cv = new ContentValues();
        cv.put("name","张三");
        cv.put("sex","男");
        cv.put("age",19);
        long rowId = db.insert("stutb",null,cv);
        cv.clear();
        cv.put("name","张三11");
        cv.put("sex","男");
        cv.put("age",22);
        db.insert("stutb",null,cv);
        cv.clear();
        cv.put("name","张三22");
        cv.put("sex","男");
        cv.put("age",33);
        db.insert("stutb",null,cv);
        cv.clear();
        cv.put("name","张三33");
        cv.put("sex","男");
        cv.put("age",44);
        db.insert("stutb",null,cv);
        cv.clear();
        cv.put("name","张三44");
        cv.put("sex","男");
        cv.put("age",55);
        db.insert("stutb",null,cv);

        cv.clear();
        cv.put("sex","女");

        db.update("stutb",cv,"_id>?",new String[]{"3"});//将ID大于三的性别全部改成女

        db.delete("stutb","name like ?",new String[]{"%11%"});//条件删除名字中带有“11”的学生

        Cursor cursor =db.query("stutb",null,"_id>?",new String[]{"0"},null,null,null);

        if (cursor!=null){
            String [] columns = cursor.getColumnNames();

            while (cursor.moveToNext()){
                for (String columnName:columns){
                    Log.d("info",cursor.getString(cursor.getColumnIndex(columnName)));
                }
            }
            cursor.close();
        }
        db.close();
    }
}
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