我正在使用SQL Server，并希望使用FileInputStream fileInputStream = new FileInputStream(selectedFile);
URL url = new URL(SERVER_URL);
connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);//Allow Inputs
connection.setDoOutput(true);//Allow Outputs
connection.setUseCaches(false);//Don't use a cached Copy
connection.setRequestMethod("POST");
connection.setRequestProperty("Connection", "Keep-Alive");
connection.setRequestProperty("ENCTYPE", "multipart/form-data");
connection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
//creating new dataoutputstream
dataOutputStream = new DataOutputStream(connection.getOutputStream());
//writing bytes to data outputstream
dataOutputStream.writeBytes(twoHyphens + boundary + lineEnd);
dataOutputStream.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename=\""
+ selectedFilePath + "\"" + lineEnd);
dataOutputStream.writeBytes(lineEnd);
//returns no. of bytes present in fileInputStream
bytesAvailable = fileInputStream.available();
//selecting the buffer size as minimum of available bytes or 1 MB
bufferSize = Math.min(bytesAvailable,maxBufferSize);
//setting the buffer as byte array of size of bufferSize
buffer = new byte[bufferSize];
//reads bytes from FileInputStream(from 0th index of buffer to buffersize)
bytesRead = fileInputStream.read(buffer,0,bufferSize);
//loop repeats till bytesRead = -1, i.e., no bytes are left to read
while (bytesRead > 0){
//write the bytes read from inputstream
dataOutputStream.write(buffer,0,bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable,maxBufferSize);
bytesRead = fileInputStream.read(buffer,0,bufferSize);
}
dataOutputStream.writeBytes(lineEnd);
dataOutputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
serverResponseCode = connection.getResponseCode();
String serverResponseMessage = connection.getResponseMessage();
Log.i(TAG, "Server Response is: " + serverResponseMessage + ": " + serverResponseCode);
//response code of 200 indicates the server status OK
if(serverResponseCode == 200){
runOnUiThread(new Runnable() {
@Override
public void run() {
tvFileName.setText("File Upload completed.\n\n You can see the uploaded file here: \n\n" + "http://coderefer.com/extras/uploads/"+ fileName);
}
});
}
//closing the input and output streams
fileInputStream.close();
dataOutputStream.flush();
dataOutputStream.close();
表中保存的该供应商的最新发票日期来更新Suppliers表。
我尝试过：
invoices但这只是从整个UPDATE Suppliers
SET Last_Billed_Date = (SELECT MAX(invoice_date) as 'MAXDATE'
FROM Invoices i
INNER JOIN Suppliers s
ON i.supplierID=s.id
)
表中返回MAX日期。
答案 0 :(得分：1)
您可以使用相关子查询来做您想做的事情：
UPDATE Suppliers
SET Last_Billed_Date = (SELECT MAX(i.invoice_date)
FROM Invoices i
WHERE i.supplierID = Suppliers.id);
子查询中不需要JOIN。
答案 1 :(得分：0)
尝试一下：
UPDATE f1
SET f1.Last_Billed_Date = MAX(f2.invoice_date)
FROM Suppliers f1 INNER JOIN Invoices f2 ON f2.supplierID = f1.id
答案 2 :(得分：0)
UPDATE Suppliers S
SET S.Last_Billed_Date = (SELECT MAX(i.invoice_date)
FROM Invoices i
WHERE i.supplierID = S.supplierID );