问题描述
我有一个JSONStore用于客户列表，用户可以使用该应用程序向这些客户添加文档。
I have a JSONStore for a list of customers, the user can add documents to those customers using the app.
cusotmer及其数据列表（也附上）文件）必须与后端同步。
The list of cusotmers and its data (also attached documents) must be synch with the backend.
当我将一个ppt文档774KB（即二进制文件的大小，我将其转换为base64）添加到json商店时执行push（）失败并显示错误：
When I add a ppt document 774KB (that is the size in binary, I transform it to base64) to the json store and execute the push() it fails with the error:
E/CursorWindow(32705): need to grow: mSize = 1048576, size = 1056310, freeSpace() = 1048464, numRows = 1
E/CursorWindow(32705): Attempting to grow window beyond max size (1048576)
E/Cursor(32705): Failed allocating 1056310 bytes for text/blob at 0,1
D/Cursor(32705): finish_program_and_get_row_count row 0
E/CursorWindow(32705): need to grow: mSize = 1048576, size = 1056310, freeSpace() = 1048464, numRows = 1
E/CursorWindow(32705): Attempting to grow window beyond max size (1048576)
E/Cursor(32705): Failed allocating 1056310 bytes for text/blob at 0,1
D/Cursor(32705): finish_program_and_get_row_count row 0
E/CursorWindow(32705): Bad request for field slot 0,0. numRows = 0, numColumns = 4
E/jsonstore-core(32705): error while dispatching action "allDirty"
E/jsonstore-core(32705): java.lang.IllegalStateException: get field slot from row 0 col 0 failed
E/jsonstore-core(32705): at net.sqlcipher.CursorWindow.getLong_native(Native Method)
E/jsonstore-core(32705): at net.sqlcipher.CursorWindow.getLong(CursorWindow.java:381)
E/jsonstore-core(32705): at net.sqlcipher.AbstractWindowedCursor.getLong(AbstractWindowedCursor.java:110)
E/jsonstore-core(32705): at net.sqlcipher.AbstractCursor.moveToPosition(AbstractCursor.java:195)
E/jsonstore-core(32705): at net.sqlcipher.AbstractCursor.moveToNext(AbstractCursor.java:257)
E/jsonstore-core(32705): at android.database.CursorWrapper.moveToNext(CursorWrapper.java:166)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.AllDirtyActionDispatcher$AllDirtyAction.performAction(AllDirtyActionDispatcher.java:148)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.AllDirtyActionDispatcher$AllDirtyAction.performAction(AllDirtyActionDispatcher.java:119)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.DatabaseActionDispatcher$Context.performReadableDatabaseAction(DatabaseActionDispatcher.java:141)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.AllDirtyActionDispatcher.dispatch(AllDirtyActionDispatcher.java:64)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.DatabaseActionDispatcher.dispatch(DatabaseActionDispatcher.java:56)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.BaseActionDispatcher.dispatch(BaseActionDispatcher.java:87)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.DispatchingPlugin$ActionDispatcherRunnable.run(DispatchingPlugin.java:113)
E/jsonstore-core(32705): at com.worklight.androidgap.plugin.storage.DispatchingPlugin$SerialExecutor$1.run(DispatchingPlugin.java:147)
E/jsonstore-core(32705): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
E/jsonstore-core(32705): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
E/jsonstore-core(32705): at java.lang.Thread.run(Thread.java:856)
E/myApp (32705): [wl.jsonstore] {"src":"push","err":8,"msg":"FAILED_TO_GET_UNPUSHED_DOCUMENTS_FROM_DB","col":"Documentos","usr":"jsonstore","doc":{},"res":{}}
我可以添加该文档，错误正在执行push（）方法。
I can add the document, the error is executing the push() method.
我在stackoverflow和infocenter中看到的关于JSONStore的所有信息都是没有大小限制。我的手机里有足够的可用空间。
All the information I have seen in stackoverflow and infocenter about JSONStore is that there is no size limit. I have more than enough free space in my mobile.
任何想法？
谢谢。
推荐答案
不要在数据库中存储blob [...]。将标识符存储在数据库中并将blob作为文件到存储。 -
Cordova有一个可以使用的。
Cordova has a File API you can use.
这是一个简单的例子：
//Code to write customer-1-file1.ppt and customer-1-file2.ppt to disk.
//See Cordova's File API.
//Pseudocode to get the blobsCollection and add metadata to be able to find the files.
//This would be inside the success callback for writing the files.
WL.JSONStore.get('blobsCollection')
.add([{fileName: 'customer-1-file1.ppt'}, {fileName: 'customer-1-file2.ppt'}]);
//Some time has passed...
//Pseudocode to get %customer-1% from disk
//% are wildcards characters and match any string
WL.JSONStore.get('blobsCollection')
.find({fileName: 'customer-1'}, {exact: false})
.then(function (listOfFiles) {
//listOfFiles => [{_id: 1, json: { fileName: 'customer-1-file1.ppt'} },
// {_id: 2, json: { {fileName: 'customer-1-file2.ppt'} }]
var firstFile = listOfFiles[0].json.fileName;
//Code to read firstFile. See Cordova's File API.
});
JSONStore由SQLite支持（技术上很好，它是添加数据加密的SQLite的包装器。阅读。外卖是对于小于100KB的BLOB，当BLOB直接存储在数据库文件中时读取速度更快。对于大于100KB的BLOB，从单独的文件读取更快。
JSONStore is backed by SQLite (well, technically SQLCipher which is a wrapper for SQLite that adds data encryption). Read Internal Versus External BLOBs in SQLite. The takeaway is "For BLOBs smaller than 100KB, reads are faster when the BLOBs are stored directly in the database file. For BLOBs larger than 100KB, reads from a separate file are faster".
如果你需要存储大于默认SQLite游标大小（1048576字节）的blob，我建议。
If you need to store blobs bigger than the default SQLite Cursor size (1048576 bytes), I suggest a feature request here.
我会确保在文档中提到这一点。
I'll make sure this is mentioned in the documentation.
请注意，有一个可用于获取的API push API将尝试发送到Worklight Adapter的文档列表。您需要使用 WL.Client.invokeProcedure 自行将文件更改发送到Worklight Adapter，或者使用 jQuery.ajax 。
Note that there's a getPushRequired API you can use to get the list of documents that the push API will try to send to the Worklight Adapter. You will need to send file changes yourself to the Worklight Adapter using WL.Client.invokeProcedure, or directly to a backend using something like jQuery.ajax.
这篇关于使用带文件的文档推送集合时出现JSONStore错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！