3 interface instructions

3.1 data definition interface (DDL)

3.1.1 create database

3.1.1.1 create database

3.1.1.2 example code

The DataSongClient driver package is introduced and implemented as follows:

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
boolean result = dataSongClient.createDB(dbName);
System.out.println(result);

Note: dbName can only contain letters or numbers and cannot start with a number

3.1.2 create data table

3.1.2.1 interface description

3.1.2.2 example code

The DataSongClient driver package is introduced and implemented as follows:

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);

dataSongClient.setDatabaseName(dbName);//Note that you need to specify a database

boolean result = dataSongClient.createTable(Student.class);
System.out.println(result);

Note 1: when you use the dataSongClient instance for the first time, you need to specify the database for operation once.
Note 2: the table can be created automatically through class. Student is defined as follows:

@DSStoreType(StoreType.Fulltext)//Specify the storage type of the table, such as fulltext, sql, etc
@DSTableName(value = "student")//Specify the database name, but not specified. The class name will be used automatically by default
public class Student extends DataSongBean {
    @DSFulltextIndexType(FulltextIndexType.None)//Set storage only, not index, that is, it can not be retrieved as a condition, saving storage space
    private String classid;

    @DSFulltextIndexType(FulltextIndexType.None)
    private Date createtime;

@DSFulltextIndexType(FulltextIndexType.Whitespace)//Set space participle
    private String interest;

    @DSFulltextIndexType (FulltextIndexType.IK)  //Set Chinese word segmentation
    private String name;

    private int age;//Not set, retrievable by default

    @DSFulltextIndexType(FulltextIndexType.None)
    private Date birth;
}

1) An internal unique id is built into the DataSongBean_ id, that is, all DataSong tables will have a built-in unique id.
2) All annotations of DataSong start with "DS" and are divided into class level and attribute level, as shown in the following figure:

Different storage types (DSStoreType) should correspond to different index types (DSFulltextIndexType, DSGraphIndexType, dsmmemindextype, DSNoSqlIndexType, DSSqlIndexType). Other attribute level annotations do not distinguish between storage types.

3.1.3 delete data table

3.1.3.1 interface description

3.1.3.2 example code

The DataSongClient driver package is introduced and implemented as follows:

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);

dataSongClient.setDatabaseName(dbName);//Note that you need to specify a database

boolean result = dataSongClient.deleteTable(Student.class);
System.out.println(result);

Note: this deletion is a physical deletion. Once deleted, it cannot be restored.

3.1.4 delete database

3.1.4.1 interface description

3.1.4.2 example code

The DataSongClient driver package is introduced and implemented as follows:

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);

boolean result = dataSongClient.deleteDB(dbName);

System.out.println(result);

Note: this deletion is a physical deletion. Once deleted, it cannot be restored.

3.2 data operation interface (DML)

3.2.1 data query interface

3.2.1.1 interface description

The internal query system is as follows:

3.2.1.2 example code

(1) Query condition construction
Exact match condition:

//Writing method 1.1
TermSearchCondition term = new TermSearchCondition();
        term.setValue(new int[]{ 6, 7});
        term.setColumn("age");



//Writing 1.2
TermSearchCondition ageTermSearchCondition  = ConditionBuilder.termCondition("age",  7);




//Writing 2.1
TermSearchCondition interestTermSearchCondition  = ConditionBuilder.termCondition("interest", new String[]{"high jump","Basketball"});



//Writing 2.2
TermSearchCondition interestTermSearchCondition  = ConditionBuilder.termCondition("interest", "High jump basketball");//The query criteria will also be automatically segmented

Range query criteria

//Writing method 1
RangeSearchCondition rangeSearchCondition = new RangeSearchCondition();
      rangeSearchCondition.setFrom("2021-02-07 18:25:04");
//    rangeSearchCondition.setTo("2021-02-07 18:25:05.6");// You can set limits on only one side
      rangeSearchCondition.setColumn("createtime");


     
//Writing method 2
RangeSearchCondition   createtimeRangeSearchCondition = ConditionBuilder.rangeCondition("createtime","2021-03-06 8:25", "2021-03-06 18:25:05.6");

Bool query criteria

BoolSearchCondition boolSearchCondition = new BoolSearchCondition();
      boolSearchCondition.must(rangeSearchCondition);//.must(ageTermSearchCondition).must(createtimeRangeSearchCondition);

(2) Construction of statistical conditions
Note: statistics the distribution of data in the dataset that meets the query criteria. Basic single value statistics cannot be cascaded at multiple levels. Grouping statistics supports multi-level cascading, which can be compared with SQL query. The statistical result is returned in the form of table, which can also be compared with SQL query. All statistics need to set an alias. Alias cannot be repeated for multiple conditions in the same query.

Mean statistics

//Writing method 1
AvgStatisticCondition avgStatisticCondition = new AvgStatisticCondition();
avgStatisticCondition.setAlias("avg");
avgStatisticCondition.setColumn("age");
//Writing method 2
AvgStatisticCondition c1 = ConditionBuilder.avgStatisticCondition("age", "Average statistics");

Summation statistics

//Writing method 1
SumStatisticCondition sumStatisticCondition = new SumStatisticCondition();
sumStatisticCondition.setAlias("sum");
sumStatisticCondition.setColumn("age");

//Writing method 2
SumStatisticCondition c2 = ConditionBuilder.sumStatisticCondition("age", "Summation statistics");

Count statistics

CountStatisticCondition c4 = ConditionBuilder.countStatisticCondition("age", "count Statistics");

Group statistics by date interval - setting the next level is supported

//For the createtime column, statistics are grouped by day
DateRangeStatisticCondition dateRangeStatisticCondition = ConditionBuilder.dateRangeStatisticCondition("createtime", "time_statistic", DateInterval.Day);

//Next level statistics can be set for date range
dateRangeStatisticCondition.addChild(c4);
dateRangeStatisticCondition.addChild(c5);

Group statistics by type - supports setting the next level

//For the interest column, group statistics
TermStatisticCondition termStatisticCondition = ConditionBuilder.termStatisticCondition

      termStatisticCondition.setColumn("interest");
      termStatisticCondition.setAlias("alias");
      termStatisticCondition.addChild(c4);
      termStatisticCondition.addChild(sumStatisticCondition);

(3) Inquiry

SearchDataRequest searchDataRequest = new SearchDataRequest();

//Set query criteria
searchDataRequest.setSearch(boolSearchCondition);
//Adding statistical conditions allows multiple statistical conditions to be set in parallel, and the index adopts the add method
      searchDataRequest.addStatistic(c3);

//Set paging
      searchDataRequest.setStart(0);
      searchDataRequest.size(5);

      //Set sort
      searchDataRequest.sort("birth", SortOrder.ASC);
      searchDataRequest.sort("createtime", SortOrder.DESC);

      //Set the columns to be fetched
searchDataRequest.setColumns(new String[] {"interest"});//Return all columns without setting default

      DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip, port);
      dataSongClient.setDatabaseName(dbName);

        DataSongSearchResult response = dataSongClient.getDataService().searchData(Student.class ,searchDataRequest);//If you set an entity class, it will be flipped automatically

//Total hits
      System.out.println("Total number of qualified articles:"+response.getTotal());
      
//Parse query results (if any)
for(int i = 0 ; i <response.getItems().size(); i++) {
         System.out.println(DataSongJsonUtils.toJson(response.getItems().get(i)));
      }

//Parse Statistics (if any)
//The return structure is encapsulated into the same structure (i.e. table structure) as the ResultSet in the jdbc protocol
for(int index = 0 ;  index < response.getStatistics().size() ; index++){
   DataSongResultSet resultSet = (DataSongResultSet) response.getStatistics().get(index);

//Header resolution, that is, user-defined alias
   ResultSetMetaData rsmd = resultSet.getMetaData();
   for (int i = 1; i <= rsmd.getColumnCount(); i++) {
      System.out.print(rsmd.getColumnName(i)+"\t\t");
   }
   System.out.println();

//Structural analysis
   while(resultSet.next()){
      for(int i=1;i<=rsmd.getColumnCount();i++){
         System.out.print(resultSet.getObject(i));
         System.out.print("\t\t");
      }

      System.out.println();
   }
}

3.2.1 data insertion and modification

3.2.1.1 interface description

3.2.1.2 example code

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
      dataSongClient.setDatabaseName("test");

      StudentBean studentBean = new StudentBean();
//    studentBean.set_id("1"); // Not required
      studentBean.setAge(2);
      studentBean.setClassid("sdf");
      studentBean.setCreatetime(new Date());
      studentBean.setName("sdfssdfdf");
        studentBean.setInterest("Football basketball table tennis");

dataSongClient.getDataService().saveData("StudentBean",studentBean); //For the same_ id data will be overwritten directly. Therefore, when modifying data, you need to bring the fields that do not need to be modified and follow the rest specification.

//Batch insert
List<StudentBean> datas = new ArrayList<>();
dataSongClient.getDataService().batchSaveData( datas);

Note: the table name is not required to be displayed during insertion. The corresponding table name can be automatically resolved according to the data type.

3.2.2 data deletion

3.2.2.1 interface description

3.2.2.2 example code

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

boolean result = dataSongClient.getDataService().deleteData(StudentBean.class, "11"); //The table name can be a class or a string

System.out.println(result);



//Batch deletion is written as follows:
List<String> ids = Arrays.asList(new String[]{"11","12","13"});
long result = dataSongClient.getDataService().batchDeleteData(StudentBean.class, ids); //The library name can be a class or a string

3.2.3 data retrieval

The old version interface has more functions and is cumbersome to use. It is not recommended.

3.2.4 data acquisition

3.2.4.1 interface description

3.2.4.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");//Real database name

StudentBean result = dataSongClient.getDataService().getData(StudentBean.class, "1"); //The table name can be a class or a string. If it is a string, the json format is returned

System.out.println( DataSongJsonUtils.toJson(result));


//For batch acquisition, write as follows
List<String> ids = Arrays.asList(new String[]{"1","2","3"});
List<StudentBean> result = dataSongClient.getDataService().batchGetData(StudentBean.class, ids); //The table name can be a class or a string

3.2.5 data clearing

3.2.5.1 interface description

3.2.5.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

boolean result = dataSongClient.getDataService().clearData(StudentBean.class); //The table name can be a class or a string

System.out.println( result);

3.3 document operation interface

3.3.1 local file upload

3.3.1.1 interface description

3.3.1.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

String id = dataSongClient.getFileService().uploadFile(StudentBean.class,"D:\\New text document.txt"); //For the same_ id data will be directly overwritten

System.out.println( id);

3.3.2 file deletion

3.3.2.1 interface description

3.3.2.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");
boolean id = dataSongClient.getFileService().deleteFile(StudentBean.class,"dddddddd");
System.out.println( id);

3.3.3 file download

3.3.3.1 interface description

3.3.3.1 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

boolean id = dataSongClient.getFileService().downloadFile(StudentBean.class,"dddddddd","d://ddd.txt");

System.out.println( id);

3.3.4 file streaming upload

3.3.4.1 interface description

3.3.4.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

FileInputStream inputStream = new FileInputStream(new File("D:\\New text document.txt"));//The stream can also be obtained through the stream returned by the browser

String id = dataSongClient.getFileService().uploadFile(StudentBean.class,"New text document.txt",inputStream); //For the same_ id data will be directly overwritten

System.out.println( id);

3.3.5 file streaming Download

3.3.5.1 interface description

3.3.5.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

InputStream inputStream = dataSongClient.getFileService().downloadFileStream(StudentBean.class,"dddddddd");

System.out.println( inputStream);

3.3.6 document preview

3.3.6.1 interface description

3.3.6.2 code example

DataSongClient dataSongClient = DataSongHttpClient.getInstance(ip,port);
dataSongClient.setDatabaseName("test");

boolean result = dataSongClient.getFileService().previewFile(StudentBean.class,"dddddddd", servletResponse);

System.out.println( result);