{"id":94,"date":"2011-04-12T22:19:48","date_gmt":"2011-04-12T14:19:48","guid":{"rendered":"http:\/\/guoh.ai\/lifelog\/?p=94"},"modified":"2011-04-12T22:19:48","modified_gmt":"2011-04-12T14:19:48","slug":"how-to-use-sqliteopenhelper","status":"publish","type":"post","link":"https:\/\/guoh.ai\/lifelog\/2011\/04\/how-to-use-sqliteopenhelper\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528SQLiteOpenHelper"},"content":{"rendered":"<p>\u90fd\u77e5\u9053\u5728Android\u4e2dSQLiteOpenHelper\u662f\u7528\u6765\u521b\u5efa\u548c\u5347\u7ea7\u6570\u636e\u5e93\uff0c\u53c2\u8003<br \/>\n$ANDROID_SDK_HOME\/docs\/reference\/android\/database\/sqlite\/SQLiteOpenHelper.html<\/p>\n<p>\u8f6f\u4ef6\u53d1\u5e03\u51fa\u53bb\u4e86\uff0c\u7528\u6237\u5df2\u7ecf\u5b89\u88c5\u4f7f\u7528\u4e86\uff0c\u4f46\u662f\u968f\u7740\u8f6f\u4ef6\u7684\u5347\u7ea7\uff0c\u6570\u636e\u5e93\u7ed3\u6784\u505a\u4e86\u4e9b\u6539\u52a8\uff0c\u6211\u4eec\u4e0d\u5e0c\u671b\u7528\u6237\u628a\u5e94\u7528\u5378\u8f7d\u4e86\u518d\u88c5(\u8fd9\u6837\u4f1a\u4e22\u5931\u5e94\u7528\u6240\u6709\u7684\u6570\u636e)\uff0c\u6211\u4eec\u5e0c\u671b\u5728\u6570\u636e\u5e93\u603b\u4f53\u7ed3\u6784\u548c\u5df2\u6709\u6570\u636e\u4e0d\u53d8\u7684\u60c5\u51b5\u4e0b\u505a\u4e9b\u5c0f\u7684\u6539\u52a8\uff0c\u6bd4\u5982\u65b0\u589e\u4e00\u4e2a\u5b57\u6bb5\u6216\u7d22\u5f15\uff0c\u65b0\u589e\u52a0\u4e00\u4e2a\u8868\u7b49\u7b49\uff0c\u90a3\u4e48\u8fd9\u4e2a\u65f6\u5019\u6211\u4eec\u5c31\u8981\u7528\u5230\u8fd9\u4e2a\u7c7b\u4e86<\/p>\n<p>\u5e38\u7528\u7684\u4e5f\u5c31\u662fonCreate\u548conUpgrade\u8fd9\u4e24\u4e2a\u65b9\u6cd5\uff0c\u5728\u4f7f\u7528\u7684\u65f6\u5019\u8fd9\u4e24\u4e2a\u65b9\u6cd5\u90fd\u9700\u8981\u91cd\u5199\uff0c\u91cc\u9762\u5b9e\u73b0\u81ea\u5df1\u7684\u903b\u8f91<\/p>\n<p>\u6211\u4eec\u5148\u5217\u51fa\u4e00\u4e2a\u573a\u666f\uff1a<br \/>\n\u5047\u8bbe\u7b2c\u4e00\u7248\u7a0b\u5e8f\u53d1\u5e03\u51fa\u53bb\uff0cFirst Public Version\uff0c\u4ee3\u7801\u5982\u4e0b<\/p>\n<pre class=\"brush: java; title: ; notranslate\" title=\"\">\t@Override\r\n\tpublic void onCreate(SQLiteDatabase db) {\r\n\t\tbootstrapDB(db);\r\n\t}\r\n\r\n\t@Override\r\n\tpublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {\r\n\t}<\/pre>\n<p>onUpgrade\u91cc\u9762\u6ca1\u6709\u4ee3\u7801\uff0c\u7b2c\u4e00\u7248\u51fa\u53bb\u6ca1\u6709\u9700\u8981\u66f4\u65b0\u7684\uff0cbootstrapDB\u65b9\u6cd5\u5c31\u662f\u4e9bDDL\u548c\u6570\u636e\u521d\u59cb\u5316\u64cd\u4f5c\u7b49\u7b49<\/p>\n<p>\u4e4b\u540e\u8fc7\u4e86\u4e00\u6bb5\u65f6\u95f4\uff0c\u65b0\u7684\u7a0b\u5e8f\u53d1\u5e03(\u5176\u4e2d\u6570\u636e\u5e93\u7ed3\u6784\u505a\u4e86\u4e9b\u53d8\u5316)\uff0c\u8fd9\u4e2a\u65f6\u5019\u5df2\u7ecf\u5f00\u59cb\u4f7f\u7528\u7b2c\u4e00\u7248\u7a0b\u5e8f\u7684\u7528\u6237\u5c31\u9700\u8981\u5347\u7ea7\uff0c\u6211\u4eec\u4e0d\u5e0c\u671b\u4ed6\u5df2\u7ecf\u5b58\u5728\u7684\u6570\u636e\u88ab\u7834\u574f\uff0c\u90a3\u4e48\u6211\u4eec\u53d1\u5e03\u51fa\u53bb\u7684\u65b0\u7684\u7248\u672c\u4e2d\u4ee3\u7801\u8be5\u600e\u4e48\u5199\u5462\uff1f<br \/>\n\u76f4\u63a5\u770b\u4ee3\u7801\uff0c\u8fd9\u4e9b\u4ee3\u7801\u90fd\u662f\u4eceAndroid\u81ea\u5e26\u7684\u5e94\u7528\u4e2d\u62bd\u53d6\u51fa\u6765\u7684\uff0c\u505a\u4e86\u4e9b\u5177\u4f53\u4e1a\u52a1\u4e0a\u7684\u7b80\u5316\uff0c\u4e3b\u8981\u662f\u9610\u8ff0\u6e05\u695a\u7528\u6cd5<\/p>\n<pre class=\"brush: java; title: ; notranslate\" title=\"\">    @Override\r\n\tpublic void onCreate(SQLiteDatabase db) {\r\n\t\tbootstrapDB(db); \/\/ \u8fd9\u4e2a\u65b9\u6cd5\u91cc\u9762\u90fd\u662f\u6700\u65b0\u7248\u7684\u521d\u59cb\u5316\u65b9\u6cd5\r\n\t}\r\n\r\n\t@Override\r\n\tpublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {\r\n\t\tLog.i(TAG, &quot;Upgrading DB from version &quot; + oldVersion + &quot; to &quot;\r\n\t\t\t\t+ newVersion);\r\n\t\tif (oldVersion == 1) {\r\n\t\t\tupgradeToVersion2(db);\r\n\t\t\toldVersion += 1;\r\n\t\t}\r\n\t\tLog.v(&quot;do upgrade&quot;, &quot;\u6211\u66f4\u65b0\u4e86\u3002\u3002\u3002&quot;);\r\n\t}<\/pre>\n<p>\u8fd9\u6837\u5982\u679c\u540e\u6765\u53c8\u6709\u65b0\u7684\u7a0b\u5e8f\u53d1\u5e03\uff0c\u90a3\u4e48\u8fd9\u4e24\u4e2a\u65b9\u6cd5\u4f1a\u53d8\u6210\u7c7b\u4f3c\u8fd9\u4e2a\u6837\u5b50<\/p>\n<pre class=\"brush: java; title: ; notranslate\" title=\"\">    @Override\r\n\tpublic void onCreate(SQLiteDatabase db) {\r\n\t\tbootstrapDB(db); \/\/ \u8fd9\u4e2a\u65b9\u6cd5\u91cc\u9762\u59cb\u7ec8\u90fd\u662f\u6700\u65b0\u7248\u7684\u521d\u59cb\u5316\u65b9\u6cd5\r\n\t}\r\n\r\n\t@Override\r\n\tpublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {\r\n\t\tLog.i(TAG, &quot;Upgrading DB from version &quot; + oldVersion + &quot; to &quot;\r\n\t\t\t\t+ newVersion);\r\n\t\tif (oldVersion == 1) {\r\n\t\t\tupgradeToVersion2(db);\r\n\t\t\toldVersion += 1;\r\n\t\t}\r\n\t\tif (oldVersion == 2) {\r\n\t\t\tupgradeToVersion3(db);\r\n\t\t\toldVersion += 1;\r\n\t\t}\r\n\t\t\/\/ \u8fd9\u662f\u4e00\u79cd\u9010\u7ea7\u66f4\u65b0\u7684\u65b9\u5f0f\r\n                \/\/ \u5bf9\u4e8e\u76ee\u524d\u4f7f\u7528\u7684\u8fd8\u662f\u7b2c\u4e00\u7248\u7684\u7528\u6237\u800c\u8a00\uff0c\u4f1a\u5148\u6267\u884c\u5b8cupgradeToVersion2\u518d\u6267\u884cupgradeToVersion3\r\n                \/\/ \u5bf9\u4e8e\u76ee\u524d\u4f7f\u7528\u7684\u8fd8\u662f\u7b2c\u4e8c\u7248\u7684\u7528\u6237\u800c\u8a00\uff0c\u4f1a\u6267\u884cupgradeToVersion3\r\n\t\tLog.v(&quot;do upgrade&quot;, &quot;\u6211\u66f4\u65b0\u4e86\u3002\u3002\u3002&quot;);\r\n\t}<\/pre>\n<p>\u8fd9\u6837\u4e5f\u8bb8\u5c31\u80fd\u770b\u7684\u5f88\u6e05\u695a\u8fd9\u4e2a\u7c7b\u7684\u610f\u56fe\u548c\u7528\u6cd5\u4e86\uff0c\u540e\u9762\u7248\u672c\u4e00\u76f4\u589e\u52a0\u7684\u8bdd\uff0c\u6211\u4eec\u5c31\u4e00\u76f4\u8fd9\u6837\u5199\u5c31\u597d\uff0c\u4fdd\u8bc1\u5168\u65b0\u7684\u7528\u6237\u548c\u5347\u7ea7\u7684\u7528\u6237\u90fd\u80fd\u6b63\u5e38\u4f7f\u7528\uff0c\u90a3\u4e48\u6211\u4eec\u5982\u4f55\u6765\u8c03\u7528\u5462<br \/>\n\u4e00\u822c\u6211\u4eec\u4f1a\u6709\u4e2a\u6784\u9020\u65b9\u6cd5\uff0c\u6709\u4e2a\u53c2\u6570\u5c31\u662f\u6570\u636e\u5e93\u7684\u7248\u672c\uff0c\u6bd4\u5982\u4e0b\u9762\u8fd9\u4e24\u4e2a\u6784\u9020\u65b9\u6cd5<\/p>\n<pre class=\"brush: java; title: ; notranslate\" title=\"\">\tpublic MyDatabaseHelper(Context context, String name, CursorFactory factory,\r\n\t\t\tint version) {\r\n\t\tsuper(context, name, factory, version);\r\n\t}\r\n\r\n\tpublic MyDatabaseHelper(Context context, int version) {\r\n\t\tsuper(context, NAME, null, version);\r\n\t}<\/pre>\n<p>\u91c7\u7528\u5982\u4e0b\u65b9\u5f0f\u8c03\u7528<\/p>\n<pre class=\"brush: java; title: ; notranslate\" title=\"\">\thelper = new MyDatabaseHelper(context, 10); \/\/ \u8fd9\u4e2a\u6570\u636e\u5e93\u7248\u672c\u53f7\u4f1a\u968f\u7740\u7a0b\u5e8f\u7684\u6bcf\u6b21\u53d1\u5e03\u800c\u53d8\u5316\uff0c\u662f\u8868\u793a\u6bcf\u6b21\u9700\u8981\u66f4\u65b0\u5230\u7684\u7248\u672c\u53f7\uff0c\u4e5f\u5c31\u662f\u6700\u65b0\u7684\u7248\u672c\u53f7\r\n\tsqlite = helper.getWritableDatabase();<\/pre>\n<p>\u5176\u5b9e\u66f4\u597d\u7406\u89e3\u8fd9\u4e2a\u7528\u6cd5\u5c31\u662f\u8bfb<a href=\"http:\/\/android.git.kernel.org\/?p=platform\/frameworks\/base.git;a=blob;f=core\/java\/android\/database\/sqlite\/SQLiteOpenHelper.java;h=b4615eb6b26140e4438d99607643c436a5da7008;hb=b417337486667a47c6e0c8430d4095e182f4aaa0\" target=\"_blank\">SQLiteOpenHelper<\/a>.getWritableDatabase\u8fd9\u4e2a\u65b9\u6cd5\uff0c\u91cc\u9762\u6709\u6bb5\u4ee3\u7801<\/p>\n<pre class=\"brush: java; title: ; notranslate\" title=\"\">    int version = db.getVersion();\r\n    if (version != mNewVersion) {\r\n        db.beginTransaction();\r\n        try {\r\n            if (version == 0) {\r\n                onCreate(db);\r\n            } else {\r\n                onUpgrade(db, version, mNewVersion);\r\n            }\r\n            db.setVersion(mNewVersion);\r\n            db.setTransactionSuccessful();\r\n        } finally {\r\n            db.endTransaction();\r\n        }\r\n    }<\/pre>\n<p>\u53e6\u5916\uff0c\u770b\u770bset\/get Version\u5c31\u77e5\u9053\u6570\u636e\u5e93\u7248\u672c\u6807\u8bb0\u662f\u901a\u8fc7PRAGMA user_version;\u8fd9\u4e2a\u547d\u4ee4\u6765\u5b8c\u6210\u7684\uff0c\u4f60\u4e5f\u53ef\u4ee5\u7528sqlite3\u4e4b\u7c7b\u7684\u5de5\u5177\u628a\u6570\u636e\u5e93\u6587\u4ef6\u6253\u5f00\uff0c\u7136\u540e\u6267\u884cPRAGMA user_version\u67e5\u770b\u6216\u8005\u8bbe\u7f6e\u7248\u672c\u503c<\/p>\n<p>\u5982\u4e0b\u662f\u5b8c\u6574\u7684\u4e24\u4e2a\u4ee3\u7801\uff0c\u662f\u76ee\u524d\u5728\u4f7f\u7528\u7684<br \/>\n<script src=\"https:\/\/gist.github.com\/915505.js\"> <\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u90fd\u77e5\u9053\u5728Android\u4e2dSQLiteOpenHelper\u662f\u7528\u6765\u521b\u5efa\u548c\u5347\u7ea7\u6570\u636e\u5e93\uff0c\u53c2\u8003 $ANDROID_SDK_HOME\/docs\/reference\/android\/database\/sqlite\/SQLiteOpenHelper.html \u8f6f\u4ef6\u53d1\u5e03\u51fa\u53bb\u4e86\uff0c\u7528\u6237\u5df2\u7ecf\u5b89\u88c5\u4f7f\u7528\u4e86\uff0c\u4f46\u662f\u968f\u7740\u8f6f\u4ef6\u7684\u5347\u7ea7\uff0c\u6570\u636e\u5e93\u7ed3\u6784\u505a\u4e86\u4e9b\u6539\u52a8\uff0c\u6211\u4eec\u4e0d\u5e0c\u671b\u7528\u6237\u628a\u5e94\u7528\u5378\u8f7d\u4e86\u518d\u88c5(\u8fd9\u6837\u4f1a\u4e22\u5931\u5e94\u7528\u6240\u6709\u7684\u6570\u636e)\uff0c\u6211\u4eec\u5e0c\u671b\u5728\u6570\u636e\u5e93\u603b\u4f53\u7ed3\u6784\u548c\u5df2\u6709\u6570\u636e\u4e0d\u53d8\u7684\u60c5\u51b5\u4e0b\u505a\u4e9b\u5c0f\u7684\u6539\u52a8\uff0c\u6bd4\u5982\u65b0\u589e\u4e00\u4e2a\u5b57\u6bb5\u6216\u7d22\u5f15\uff0c\u65b0\u589e\u52a0\u4e00\u4e2a\u8868\u7b49\u7b49\uff0c\u90a3\u4e48\u8fd9\u4e2a\u65f6\u5019\u6211\u4eec\u5c31\u8981\u7528\u5230\u8fd9\u4e2a\u7c7b\u4e86 \u5e38\u7528\u7684\u4e5f\u5c31\u662fonCreate\u548conUpgrade\u8fd9\u4e24\u4e2a\u65b9\u6cd5\uff0c\u5728\u4f7f\u7528\u7684\u65f6\u5019\u8fd9\u4e24\u4e2a\u65b9\u6cd5\u90fd\u9700\u8981\u91cd\u5199\uff0c\u91cc\u9762\u5b9e\u73b0\u81ea\u5df1\u7684\u903b\u8f91 \u6211\u4eec\u5148\u5217\u51fa\u4e00\u4e2a\u573a\u666f\uff1a \u5047\u8bbe\u7b2c\u4e00\u7248\u7a0b\u5e8f\u53d1\u5e03\u51fa\u53bb\uff0cFirst Public Version\uff0c\u4ee3\u7801\u5982\u4e0b @Override public void onCreate(SQLiteDatabase db) { bootstrapDB(db); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } onUpgrade\u91cc\u9762\u6ca1\u6709\u4ee3\u7801\uff0c\u7b2c\u4e00\u7248\u51fa\u53bb\u6ca1\u6709\u9700\u8981\u66f4\u65b0\u7684\uff0cbootstrapDB\u65b9\u6cd5\u5c31\u662f\u4e9bDDL\u548c\u6570\u636e\u521d\u59cb\u5316\u64cd\u4f5c\u7b49\u7b49 \u4e4b\u540e\u8fc7\u4e86\u4e00\u6bb5\u65f6\u95f4\uff0c\u65b0\u7684\u7a0b\u5e8f\u53d1\u5e03(\u5176\u4e2d\u6570\u636e\u5e93\u7ed3\u6784\u505a\u4e86\u4e9b\u53d8\u5316)\uff0c\u8fd9\u4e2a\u65f6\u5019\u5df2\u7ecf\u5f00\u59cb\u4f7f\u7528\u7b2c\u4e00\u7248\u7a0b\u5e8f\u7684\u7528\u6237\u5c31\u9700\u8981\u5347\u7ea7\uff0c\u6211\u4eec\u4e0d\u5e0c\u671b\u4ed6\u5df2\u7ecf\u5b58\u5728\u7684\u6570\u636e\u88ab\u7834\u574f\uff0c\u90a3\u4e48\u6211\u4eec\u53d1\u5e03\u51fa\u53bb\u7684\u65b0\u7684\u7248\u672c\u4e2d\u4ee3\u7801\u8be5\u600e\u4e48\u5199\u5462\uff1f \u76f4\u63a5\u770b\u4ee3\u7801\uff0c\u8fd9\u4e9b\u4ee3\u7801\u90fd\u662f\u4eceAndroid\u81ea\u5e26\u7684\u5e94\u7528\u4e2d\u62bd\u53d6\u51fa\u6765\u7684\uff0c\u505a\u4e86\u4e9b\u5177\u4f53\u4e1a\u52a1\u4e0a\u7684\u7b80\u5316\uff0c\u4e3b\u8981\u662f\u9610\u8ff0\u6e05\u695a\u7528\u6cd5 @Override public void onCreate(SQLiteDatabase db) { bootstrapDB(db); \/\/ \u8fd9\u4e2a\u65b9\u6cd5\u91cc\u9762\u90fd\u662f\u6700\u65b0\u7248\u7684\u521d\u59cb\u5316\u65b9\u6cd5 } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.i(TAG, &quot;Upgrading DB from version &hellip; <a href=\"https:\/\/guoh.ai\/lifelog\/2011\/04\/how-to-use-sqliteopenhelper\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">\u5982\u4f55\u4f7f\u7528SQLiteOpenHelper<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-94","post","type-post","status-publish","format-standard","hentry","category-android"],"_links":{"self":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts\/94","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/comments?post=94"}],"version-history":[{"count":8,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts\/94\/revisions"}],"predecessor-version":[{"id":102,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/posts\/94\/revisions\/102"}],"wp:attachment":[{"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/media?parent=94"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/categories?post=94"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/guoh.ai\/lifelog\/wp-json\/wp\/v2\/tags?post=94"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}