我开发了一个rest API，它从excel中读取数据并将其插入到多个数据库中。现在我的问题是我想避免从excel插入重复数据。我可以建议如何在每次迭代插入一个对象时检查数据的重复
@RequestMapping(value = "/excel", method = RequestMethod.POST, consumes = javax.ws.rs.core.MediaType.MULTIPART_FORM_DATA)
public void uploadFileHandler(@RequestParam("organization") UUID organization,
@RequestParam("file") MultipartFile file) throws IOException {
/*****GEt the organizaation id from form data and store to global variable*****/
this.OrganizationID = organization;
System.out.println("*****************************");
/***Possible output parameters from file object***/
/***Parameters required for S3 bucket upload***/
String timeStamp = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss").format(new java.util.Date());
InputStream is = file.getInputStream();
String keyname = timeStamp+file.getOriginalFilename();
String bucketname = "pharmerz-chat";
/**Call S3 upload class and upload file**/
amazons3.uploadfile(is, keyname, bucketname);
/****Get organisation object from organisation id***/
this.organization = iOrganizationRepository.findOne(organization);
/**Excel File reader**/
try {
ExcelController ex = new ExcelController();
File f1 = ex.convert(file);
// FileInputStream file = new FileInputStream(new File("E://Imp/Details.xlsx"));
XSSFWorkbook workbook = new XSSFWorkbook(f1);
XSSFSheet sheet = workbook.getSheetAt(0);
Iterator<Row> rowIterator = sheet.iterator();
rowIterator.next();
// while (rowIterator.hasNext()) {
for(int i=1;i<=51;i++){
Row row = rowIterator.next();
//For each row, iterate through each columns
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
// System.out.println("cell.getStringCellValue().length() "+cell.getStringCellValue().length());
// if( cell.getStringCellValue().length()>0){
List list = new ArrayList();
// This will change all Cell Types to String
cell.setCellType(Cell.CELL_TYPE_STRING);
switch (cell.getCellType()) {
case Cell.CELL_TYPE_BOOLEAN:
String bstring = "" + cell.getBooleanCellValue();
list.add(cell.getBooleanCellValue());
System.out.println("boolean===>>>" + cell.getBooleanCellValue() + "\t");
break;
case Cell.CELL_TYPE_NUMERIC:
String Nstring = "" + cell.getNumericCellValue();
list.add(Nstring);
break;
case Cell.CELL_TYPE_STRING:
list.add(cell.getStringCellValue());
break;
}
// }else {
// break;
// }
}
String productname = row.getCell(0).getStringCellValue();
String composition = row.getCell(1).getStringCellValue();
String productcategeory = row.getCell(2).getStringCellValue();
String uniqueproductcode = row.getCell(3).getStringCellValue();
String categeory = row.getCell(4).getStringCellValue();
String note = row.getCell(5).getStringCellValue();
// System.out.println(productname+"" +composition+"" +productcategeory+" "+uniqueproductcode+" "+categeory+" "+note);
System.out.println("productname " + productname);
System.out.println("composition " + composition);
System.out.println("productcategeory " + productcategeory);
System.out.println("uniqueproductcode " + uniqueproductcode);
System.out.println(" categeory " + categeory);
System.out.println("note " + note);
ExcelController ex1 = new ExcelController();
// ex1.InsertRowInDB3(name,email,add,company);
System.out.println("");
// Category categeoryobject=iCategoryRepository.findOne(UUID.fromString(CategeoryId));
Category categeoryobject = iCategoryRepository.findByCategory(productcategeory);
if(composition.isEmpty()){
composition=null;
}
if(uniqueproductcode.isEmpty()){
uniqueproductcode=null;
}
if(note.isEmpty()){
note=null;
}
Product product = new Product();
product.setProduct(productname);
product.setComposition(composition);
product.setCategory(categeoryobject);
product.setUpc(uniqueproductcode);
product.setNote(note);
insertProduct(product, categeory);
}
workbook.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (InvalidFormatException e) {
e.printStackTrace();
} catch (NullPointerException e) {
// e.printStackTrace();
System.out.println("data completed upload");
}
}
/**Insert product into database***/
public String insertProduct (Product product, String categeory) {
try{System.out.println("getProduct " + product.getProduct());
System.out.println("getComposition " + product.getComposition());
System.out.println("getCategory " + product.getCategory());
System.out.println("getUpc " + product.getUpc());
System.out.println("getCategory " + product.getCategory());
System.out.println("getNote " + product.getNote());
if (product.getProduct().isEmpty()) {
System.out.println("Product is empty");
return "Product is empty";
} else {
Product savedproduct = iProductRepository.save(product);
if (categeory.equalsIgnoreCase("Sale")) {
Supplier supplier = new Supplier();
supplier.setProduct(savedproduct);
supplier.setOrganization(organization);
iSupplierRepository.save(supplier);
System.out.println("Product added to supplier " + categeory);
} else if (categeory.equalsIgnoreCase("Purchase")) {
Purchaser purchaser = new Purchaser();
purchaser.setOrganization(organization);
purchaser.setProduct(savedproduct);
iPurchaserRepository.save(purchaser);
System.out.println("Product added to purchaser " + categeory);
} else {
Supplier supplier = new Supplier();
supplier.setProduct(savedproduct);
supplier.setOrganization(organization);
iSupplierRepository.save(supplier);
Purchaser purchaser = new Purchaser();
purchaser.setOrganization(organization);
purchaser.setProduct(savedproduct);
iPurchaserRepository.save(purchaser);
System.out.println("Product added to both " + categeory);
}
System.out.println("product added");
System.out.println("/************************");
System.out.println(savedproduct.getId());
}
return "product added";}
catch (Exception e){
// e.printStackTrace();
return "all product finished";
}
}
public File convert(MultipartFile file) throws IOException {
File convFile = new File(file.getOriginalFilename());
convFile.createNewFile();
FileOutputStream fos = new FileOutputStream(convFile);
fos.write(file.getBytes());
fos.close();
return convFile;
}
答案 0 :(得分：1)
您需要阅读数据库设计并正确实施数据定义（例如，您的记录的主键是什么......）。如果没有正确的关系数据库设计，您就无法使用Oracle的声明性功能（即无需编写代码）（例如主键，......）。
话虽如此，如果您需要，可以通过识别复制并删除它们来删除复制品，例如：
select c1, c1, c3 /* ... cn */ , count(*), min(rowid), max(rowid)
from t
group by c1, c1, c3 /* ... cn */
having count(*) > 1
;
然后删除重复项，以便只剩下1个。