Android DataProvider和数据库相关知识应用

1.创建数据库辅助类，用于创建数据库

public final class DvbDatabaseHelper extends SQLiteOpenHelper {

    /** 数据库版本号。每当修改数据库结构后，均需要对版本号递增1。 */
    public static final int DB_VERSION = 68; //Database version!!!
private Context mContext = null;

public DvbDatabaseHelper(Context context) {
        super(context, "dvb"/*location*/, null, DB_VERSION);
        mContext = context;
        sLog.LOGI("DvbDatabaseHelper(): create DvbDatabaseHelper! "
                + "ProjectName=" + Config.getInstance().getProjectName()
                + ", DBLocation=" + Config.getInstance().getDBLocation()
                + ", Verion=" + DB_VERSION);
    }

//onCreate中执行创建sql
db.execSQL(DvbDataContent.DATA_TABLE_PROGRAMS);

//onUpgrade中再次执行创建的sql

// 开启外键表约束

public static final String FOREIGN_KEYS_ON = "pragma foreign_keys = on;";

db.execSQL(DvbDataContent.FOREIGN_KEYS_ON);

//所有创建更新sql最好进行异常会滚，放入try catch

try {
initData();
db.beginTransaction();

db.execSQL("....");

            db.setTransactionSuccessful();
            db.endTransaction();
        } catch (Exception e) {
            sLog.LOGE("delete dvb database table error!");
        }

//创建一个具有外键约束的表

    /** 创建数据表： Data_Table_Crc32 */
    private void createTableCrc32() {
        DvbDataContent.DATA_TABLE_CRC32 = "create table "
                + DvbDataContent.TABLE_CRC32 + "(";
        {/* 列定义 */
            DvbDataContent.DATA_TABLE_CRC32 += (""
                    + Program.TableCrc32Columns.ID           + " integer PRIMARY KEY autoincrement, "
                    + Program.TableCrc32Columns.TpKey        + " integer NOT NULL, "
                    + Program.TableCrc32Columns.TableId      + " integer NOT NULL, "
                    + Program.TableCrc32Columns.SectionNum   + " integer NOT NULL, "
                    + Program.TableCrc32Columns.Crc32        + " integer NOT NULL, "

                    + Program.TableProgramsColumns.SERVICE_NAME             + " varchar DEFAULT 'n/a', "
                    );
        }
        {/* 外键约束 */
            DvbDataContent.DATA_TABLE_CRC32 += ""
                    + " constraint fk_TableCrc32_tp foreign key("
                    + Program.TableCrc32Columns.TpKey
                    + ") references " + DvbDataContent.TABLE_TRANSPONDERS
                    + "(_id) on delete cascade on update cascade";      // crc32表的外键tpkey依赖与tranponder表id字段，随之更新和删除还可以+ on insert cascade
        }
        DvbDataContent.DATA_TABLE_CRC32 += " )";

       {/* 值合法性检查检查 */
            DvbDataContent.DATA_TABLE_ELEMENT_STREAM += (""
            /* 基本流的pid值有效范围 */
            + "constraint ck_StreamPid CHECK(" + Program.TableElementStreamCloumns.STREAM_PID + " >= 0 " +
                    " AND " + Program.TableElementStreamCloumns.STREAM_PID +" <= 8191), "); //ck_StreamPid为自定义检查名称
        }
    }

    /** 创建视图: View_Transponders */
    private void createViewTransponders() {
        DvbDataContent.DATA_VIEW_TRANSPONDERS = "create view "
                + DvbDataContent.VIEW_TRANSPONDERS + " as select "
                + DvbDataContent.TABLE_TRANSPONDERS + ".*" + ", "
                + DvbDataContent.TABLE_NETWORKS + ".*" + " from "
                + DvbDataContent.TABLE_TRANSPONDERS + ", "
                + DvbDataContent.TABLE_NETWORKS + " where "
                + DvbDataContent.TABLE_TRANSPONDERS + "."
                + Program.TableTranspondersColumns.NETWORKS_ID + " = "
                + DvbDataContent.TABLE_NETWORKS + "._id";
    }

        // 频道-对应nvod信息级联删除触发器
        DvbDataContent.DATA_TRIGGER_PROGRAM_NVOD_DEL = "CREATE TRIGGER "
                + DvbDataContent.TRIGGER_PROGRAM_NVOD_DEL
                + " BEFORE DELETE ON " + DvbDataContent.TABLE_PROGRAMS
                + " FOR EACH ROW BEGIN " + "delete from "
                + DvbDataContent.TABLE_NVOD + " where "
                + Program.TableNvodColumns.REFERENCE_IDENT + "=old."
                + Program.TableProgramsColumns.ID + " or "
                + Program.TableNvodColumns.TIMESHIFTED_IDENT + "=old."
                + Program.TableProgramsColumns.ID + "; END;";

        // 插入节目分类信息元素，关键字段数据重复检测触发器
        DvbDataContent.DATA_TRIGGER_BOUQUET_ADD = "CREATE TRIGGER "
                + DvbDataContent.TRIGGER_BOUQUET_ADD + " BEFORE INSERT ON "
                + DvbDataContent.TABLE_BOUQUETS + " FOR EACH ROW BEGIN "
                + "SELECT RAISE(FAIL,'insert failed') WHERE EXISTS(select "
                + Program.TableBouquetsColumns.BOUQUET_ID + " from "
                + DvbDataContent.TABLE_BOUQUETS + " where "
                + Program.TableBouquetsColumns.BOUQUET_ID + " = new."

+ Program.TableBouquetsColumns.BOUQUET_ID + "); END;";

SAX解析器使用：

        SAXParserFactory spf = SAXParserFactory.newInstance(); // 初始化sax解析器
        SAXParser sp = spf.newSAXParser(); // 创建sax解析器
        DvbXmlContentHandler handler = new DvbXmlContentHandler(db);
        sp.parse(inputStream, handler);

write somethings into Setting :

1.add permission

<uses-permission android:name="android.permission.WRITE_SETTINGS"></uses-permission>

2.add

Settings.System.putString(mContext.getContentResolver(), "key" , (String)oneValues.getValue());

//annouce provider package&class path and authorities

Android DataProvider和数据库相关知识应用

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