Android數據庫(SqlLite)操作和db文件查看操作步驟很簡單,首先導入sqlLite 的DB文件(即File Explorer /data /data/),然後進行各種sql操作。
下面是我的代碼:
- package com.xiaoshan.udp.client.db;
-
- import android.content.ContentValues;
- import android.content.Context;
- import android.database.Cursor;
- import android.database.SQLException;
- import android.database.sqlite.SQLiteDatabase;
- import android.database.sqlite.SQLiteOpenHelper;
-
- /**
- * 數據庫常用操作的封裝類
- *
- * @author 單紅宇
- *
- */
- public class DBHelper {
-
- private static DatabaseHelper mDbHelper;
- private static SQLiteDatabase mDb;
-
- private static final String DATABASE_NAME = "shanhy.db";
-
- private static final int DATABASE_VERSION = 1;
-
- private final Context mCtx;
-
- private static class DatabaseHelper extends SQLiteOpenHelper {
-
- DatabaseHelper(Context context) {
- super(context, DATABASE_NAME, null, DATABASE_VERSION);
- }
-
- @Override
- public void onCreate(SQLiteDatabase db) {
- }
-
- @Override
- public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
- }
- }
-
- public DBHelper(Context ctx) {
- this.mCtx = ctx;
- }
-
- public DBHelper open() throws SQLException {
- mDbHelper = new DatabaseHelper(mCtx);
- mDb = mDbHelper.getWritableDatabase();
- return this;
- }
-
- /**
- * 關閉數據源
- *
- * @author SHANHY
- */
- public void closeConnection() {
- if (mDb != null && mDb.isOpen())
- mDb.close();
- if (mDbHelper != null)
- mDbHelper.close();
- }
-
- /**
- * 插入數據 參數
- *
- * @param tableName
- * 表名
- * @param initialValues
- * 要插入的列對應值
- * @return
- * @author SHANHY
- */
- public long insert(String tableName, ContentValues initialValues) {
-
- return mDb.insert(tableName, null, initialValues);
- }
-
- /**
- * 刪除數據
- *
- * @param tableName
- * 表名
- * @param deleteCondition
- * 條件
- * @param deleteArgs
- * 條件對應的值(如果deleteCondition中有“?”號,將用此數組中的值替換,一一對應)
- * @return
- * @author SHANHY
- */
- public boolean delete(String tableName, String deleteCondition, String[] deleteArgs) {
-
- return mDb.delete(tableName, deleteCondition, deleteArgs) > 0;
- }
-
- /**
- * 更新數據
- *
- * @param tableName
- * 表名
- * @param initialValues
- * 要更新的列
- * @param selection
- * 更新的條件
- * @param selectArgs
- * 更新條件中的“?”對應的值
- * @return
- * @author SHANHY
- */
- public boolean update(String tableName, ContentValues initialValues, String selection, String[] selectArgs) {
- return mDb.update(tableName, initialValues, selection, selectArgs) > 0;
- }
-
- /**
- * 取得一個列表
- *
- * @param distinct
- * 是否去重復
- * @param tableName
- * 表名
- * @param columns
- * 要返回的列
- * @param selection
- * 條件
- * @param selectionArgs
- * 條件中“?”的參數值
- * @param groupBy
- * 分組
- * @param having
- * 分組過濾條件
- * @param orderBy
- * 排序
- * @return
- * @author SHANHY
- */
- public Cursor findList(boolean distinct, String tableName, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit) {
-
- return mDb.query(distinct, tableName, columns, selection, selectionArgs, groupBy, having, orderBy, limit);
- }
-
- /**
- * 取得單行記錄
- *
- * @param tableName
- * 表名
- * @param columns
- * 獲取的列數組
- * @param selection
- * 條件
- * @param selectionArgs
- * 條件中“?”對應的值
- * @param groupBy
- * 分組
- * @param having
- * 分組條件
- * @param orderBy
- * 排序
- * @param limit
- * 數據區間
- * @param distinct
- * 是否去重復
- * @return
- * @throws SQLException
- * @author SHANHY
- */
- public Cursor findOne(boolean distinct,String tableName, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit) throws SQLException {
-
- Cursor mCursor = findList(distinct, tableName, columns, selection, selectionArgs, groupBy, having, orderBy, limit);
-
- if (mCursor != null) {
- mCursor.moveToFirst();
- }
- return mCursor;
-
- }
-
- /**
- * 執行SQL(帶參數)
- *
- * @param sql
- * @param args
- * SQL中“?”參數值
- * @author SHANHY
- */
- public void execSQL(String sql, Object[] args) {
- mDb.execSQL(sql, args);
-
- }
-
- /**
- * 執行SQL
- *
- * @param sql
- * @author SHANHY
- */
- public void execSQL(String sql) {
- mDb.execSQL(sql);
-
- }
-
- /**
- * 判斷某張表是否存在
- *
- * @param tabName
- * 表名
- * @return
- */
- public boolean isTableExist(String tableName) {
- boolean result = false;
- if (tableName == null) {
- return false;
- }
-
- try {
- Cursor cursor = null;
- String sql = "select count(1) as c from sqlite_master where type ='table' and name ='" + tableName.trim() + "'";
- cursor = mDb.rawQuery(sql, null);
- if (cursor.moveToNext()) {
- int count = cursor.getInt(0);
- if (count > 0) {
- result = true;
- }
- }
-
- cursor.close();
- } catch (Exception e) {
- }
- return result;
- }
-
- /**
- * 判斷某張表中是否存在某字段(注,該方法無法判斷表是否存在,因此應與isTableExist一起使用)
- *
- * @param tabName
- * 表名
- * @param columnName
- * 列名
- * @return
- */
- public boolean isColumnExist(String tableName, String columnName) {
- boolean result = false;
- if (tableName == null) {
- return false;
- }
-
- try {
- Cursor cursor = null;
- String sql = "select count(1) as c from sqlite_master where type ='table' and name ='" + tableName.trim() + "' and sql like '%" + columnName.trim() + "%'";
- cursor = mDb.rawQuery(sql, null);
- if (cursor.moveToNext()) {
- int count = cursor.getInt(0);
- if (count > 0) {
- result = true;
- }
- }
-
- cursor.close();
- } catch (Exception e) {
- }
- return result;
- }
-
- }