SQLite 基本操作（增删改查）

当你还不能写出自己满意的程序时，你就不要去睡觉。

public class DBOpenHelper extends SQLiteOpenHelper{

public DBOpenHelper(Context context, String name) {
super(context, name, null, 1);
// TODO Auto-generated constructor stub
}
public DBOpenHelper(Context context, String name, CursorFactory factory,
int version) {
super(context, name, factory, version);
// TODO Auto-generated constructor stub
}
@Override//首次创建数据库的时候调用 一般可以把建库 建表的操作
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
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)");
db.execSQL("insert into stutb(name,sex,age)values('张三','女',18)");
}
@Override//当数据库的版本发生变化的时候 会自动执行
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub

}
}

查找：
private void queryall(SQLiteDatabase db) {

Cursor cusor = db.query("stutb", new String[]{"name", "sex", "age"}, null, null, null, null, "_id desc");

for (cusor.moveToFirst(); !cusor.isAfterLast(); cusor.moveToNext()) {

String id, age,name, sex;

id = cusor.getLong(cusor.getColumnIndex("id"))+"";

age = cusor.getLong(cusor.getColumnIndex("age"))+"";

name = cusor.getString(cusor.getColumnIndex("name"));

sex = cusor.getString(cusor.getColumnIndex("sex"));

Log.i("info", "id: " + id + "name" + name + "sex" + sex + "age" + age);

}

cusor.close();

}

private void qureyByName(String mName, SQLiteDatabase db) {

Cursor cusor = db.query("stutb",null, "name=?", new String[]{mName}, null, null, null);

String id, age,name, sex;

if (cusor.moveToFirst()) {

id = cusor.getLong(cusor.getColumnIndex("id"))+"";

age = cusor.getLong(cusor.getColumnIndex("age"))+"";

name = cusor.getString(cusor.getColumnIndex("name"));

sex = cusor.getString(cusor.getColumnIndex("sex"));

Toast.makeText(this, id + name + sex + age + "", Toast.LENGTH_LONG).show();

Log.i("info", "id: " + id + "name" + name + "sex" + sex + "age" + age);

} else {

Toast.makeText(this, "no query result", Toast.LENGTH_LONG).show();

}

}

增加：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 values = new ContentValues();

values.put("name", "张三");

values.put("sex", "男");

values.put("age", 19);

long rowId = db.insert("stutb", null, values);

values.clear();

删除：
db.update("stutb", values, "_id>?", new String[]{"3"});//将全部id>3的人的性别改成女

db.delete("stutb", "name like ?", new String[]{"%丰%"});//删除所有名字中带有丰的人

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

if (c!=null) {

String [] columns= c.getColumnNames();

while (c.moveToNext()) {

for (String columnName : columns) {

Log.i("info", c.getString(c.getColumnIndex(columnName)));

}

}

c.close();

}

db.close();

public class MainActivity extends Activity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

//每个程序都有自己的数据库 默认情况下是各自互相不干扰

//创建一个数据库 并且打开

SQLiteDatabase db = openOrCreateDatabase("user.db", MODE_PRIVATE, null);

db.execSQL("create table if not exists usertb (_id integer primary key autoincrement, name text not null , age integer not null , sex text not null )");

db.execSQL("insert into usertb(name,sex,age) values('张三','女',18)");

db.execSQL("insert into usertb(name,sex,age) values('李四','女',19)");

db.execSQL("insert into usertb(name,sex,age) values('王五','男',20)");

Cursor c = db.rawQuery("select * from usertb", null);

if (c!=null) {

while (c.moveToNext()) {

Log.i("info", "_id:"+c.getInt(c.getColumnIndex("_id")));

Log.i("info", "name:"+c.getString(c.getColumnIndex("name")));

Log.i("info", "age:"+c.getInt(c.getColumnIndex("age")));

Log.i("info", "sex:"+c.getString(c.getColumnIndex("sex")));

Log.i("info", "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");

}

c.close();

}

db.close();

}

public class MainActivity extends Activity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

//每个程序都有自己的数据库 默认情况下是各自互相不干扰

//创建一个数据库 并且打开

SQLiteDatabase db = openOrCreateDatabase("user.db", MODE_PRIVATE, null);

db.execSQL("create table if not exists usertb (_id integer primary key autoincrement, name text not null , age integer not null , sex text not null )");

db.execSQL("insert into usertb(name,sex,age) values('张三','女',18)");

db.execSQL("insert into usertb(name,sex,age) values('李四','女',19)");

db.execSQL("insert into usertb(name,sex,age) values('王五','男',20)");

Cursor c = db.rawQuery("select * from usertb", null);

if (c!=null) {

while (c.moveToNext()) {

Log.i("info", "_id:"+c.getInt(c.getColumnIndex("_id")));

Log.i("info", "name:"+c.getString(c.getColumnIndex("name")));

Log.i("info", "age:"+c.getInt(c.getColumnIndex("age")));

Log.i("info", "sex:"+c.getString(c.getColumnIndex("sex")));

Log.i("info", "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");

}

c.close();

}

db.close();

}

public class MainActivity extends Activity {

@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 values = new ContentValues();

values.put("name", "张三");

values.put("sex", "男");

values.put("age", 19);

long rowId = db.insert("stutb", null, values);

values.clear();

values.put("name", "张三丰");

values.put("sex", "男");

values.put("age", 99);

db.insert("stutb", null, values);

values.clear();

values.put("name", "张三疯");

values.put("sex", "男");

values.put("age", 59);

db.insert("stutb", null, values);

values.clear();

values.put("name", "张三峰");

values.put("sex", "男");

values.put("age", 39);

db.insert("stutb", null, values);

values.clear();

values.put("name", "张三封");

values.put("sex", "男");

values.put("age", 29);

db.insert("stutb", null, values);

values.clear();

values.put("sex", "女");

db.update("stutb", values, "_id>?", new String[]{"3"});//将全部id>3的人的性别改成女

db.delete("stutb", "name like ?", new String[]{"%丰%"});//删除所有名字中带有丰的人

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

if (c!=null) {

String [] columns= c.getColumnNames();

while (c.moveToNext()) {

for (String columnName : columns) {

Log.i("info", c.getString(c.getColumnIndex(columnName)));

}

}

c.close();

}

db.close();

}

}