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Updated on 2023-07-19 GMT+08:00
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Table-Related SDKs

Creating a DLI Table

DLI provides an API for creating DLI tables. You can use it to create a table for storing DLI data. Sample code is as follows:

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  private static Table createDLITable(Database database) throws DLIException {
    // Construct a table column set and instantiate the Column object to construct columns.
    List<Column> columns = new ArrayList<Column>();
    Column c1 = new Column("c1", DataType.STRING, "desc for c1");
    Column c2 = new Column("c2", DataType.INT, "desc for c2");
    Column c3 = new Column("c3", DataType.DOUBLE, "desc for c3");
    Column c4 = new Column("c4", DataType.BIGINT, "desc for c4");
    Column c5 = new Column("c5", DataType.SHORT, "desc for c5");
    Column c6 = new Column("c6", DataType.LONG, "desc for c6");
    Column c7 = new Column("c7", DataType.SMALLINT, "desc for c7");
    Column c8 = new Column("c8", DataType.BOOLEAN, "desc for c8");
    Column c9 = new Column("c9", DataType.DATE, "desc for c9");
    Column c10 = new Column("c10", DataType.TIMESTAMP, "desc for c10");
    Column c11 = new Column("c11", DataType.DECIMAL, "desc for c11");
    columns.add(c1);
    columns.add(c2);
    columns.add(c3);
    columns.add(c4);
    columns.add(c5);
    columns.add(c6);
    columns.add(c7);
    columns.add(c8);
    columns.add(c9);
    columns.add(c10);
    columns.add(c11);

    List<String> sortColumns = new ArrayList<String>();
    sortColumns.add("c1");
    String DLITblName = "tablename";
    String desc = "desc for table";
    // Call the createDLITable method of the Database object to create a DLI table.
    Table table = database.createDLITable(DLITblName, desc, columns, sortColumns);
    System.out.println(table);
    return table;
  }

The default precision of DataType.DECIMAL is (10,0). To set the precision of data of the decimal type, perform the following operation:

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Column c11 = new Column("c11", new DecimalTypeInfo(25,5), "test for c11");

Creating an OBS Table

DLI provides an API for creating OBS tables. You can use it to create a table for storing OBS data. The example code is as follows:

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private static Table createObsTable(Database database) throws DLIException {
    // Construct a table column set and instantiate the Column object to construct columns.
    List < Column > columns = new ArrayList < Column > ();
    Column c1 = new Column("c1", DataType.STRING, "desc for c1");
    Column c2 = new Column("c2", DataType.INT, "desc for c2");
    Column c3 = new Column("c3", DataType.DOUBLE, "desc for c3");
    Column c4 = new Column("c4", DataType.BIGINT, "desc for c4");
    Column c5 = new Column("c5", DataType.SHORT, "desc for c5");
    Column c6 = new Column("c6", DataType.LONG, "desc for c6");
    Column c7 = new Column("c7", DataType.SMALLINT, "desc for c7");
    Column c8 = new Column("c8", DataType.BOOLEAN, "desc for c8");
    Column c9 = new Column("c9", DataType.DATE, "desc for c9");
    Column c10 = new Column("c10", DataType.TIMESTAMP, "desc for c10");
    Column c11 = new Column("c11", DataType.DECIMAL, "desc for c11");
    columns.add(c1);
    columns.add(c2);
    columns.add(c3);
    columns.add(c4);
    columns.add(c5);
    columns.add(c6);
    columns.add(c7);
    columns.add(c8);
    columns.add(c9);
    columns.add(c10);
    columns.add(c11);
    CsvFormatInfo formatInfo = new CsvFormatInfo();
    formatInfo.setWithColumnHeader(true);
    formatInfo.setDelimiter(",");
    formatInfo.setQuoteChar("\"");
    formatInfo.setEscapeChar("\\");
    formatInfo.setDateFormat("yyyy/MM/dd");
    formatInfo.setTimestampFormat("yyyy-MM-dd HH:mm:ss");
    String obsTblName = "tablename";
    String desc = "desc for table";
    String dataPath = "OBS path";
    // Call the createObsTable method of the Database object to create an OBS table.
    Table table = database.createObsTable(obsTblName, desc, columns,StorageType.CSV , dataPath, formatInfo);
    System.out.println(table);
    return table;
}

The default precision of DataType.DECIMAL is (10,0). To set the precision of data of the decimal type, perform the following operation:

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Column c11 = new Column("c11", new DecimalTypeInfo(25,5), "test for c11");

Deleting a Table

DLI provides an API for deleting tables. You can use it to delete all the tables in a database. The example code is as follows:

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private static void deleteTables(Database database) throws DLIException {
    // Call the listAllTables interface of the Database object to query all tables.
    List<Table> tables = database.listAllTables();
    for (Table table : tables) {
    // Traverse tables and call the deleteTable interface of the Table object to delete tables.
      table.deleteTable();
      System.out.println("delete table " + table.getTableName());
    }
  }

A deleted table cannot be restored. Therefore, exercise caution when deleting a table.

Querying All Tables

DLI provides an API for querying tables. You can use it to query all tables in a database. The example code is as follows:

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  private static void listTables(Database database) throws DLIException {
    // Call the listAllTables method of the Database object to query all tables in a database.
    List<Table> tables = database.listAllTables(true);
    for (Table table : tables) {
      System.out.println(table);
    }
  }

Querying the Partition Information of a Table (Including the Creation and Modification Time of the Partition).

DLI provides an API for querying table partition information. You can use it to query the partition information (including the creation time and modification time) in the database table. The example code is as follows: 
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private static void showPartitionsInfo(DLIClient client) throws DLIException {
    String databaseName = "databasename";
    String tableName = "tablename";
    // Call the showPartitions method of the DLIClient object to query the partition information (including the partition creation and modification time) in the database table.
    PartitionResult partitionResult = client.showPartitions(databaseName, tableName);
    PartitionListInfo partitonInfos = partitionResult.getPartitions();
    // Obtain the creation and modification time of the partition.
    Long createTime = partitonInfos.getPartitionInfos().get(0).getCreateTime().longValue();
    Long lastAccessTime = partitonInfos.getPartitionInfos().get(0).getLastAccessTime().longValue();
    System.out.println("createTime:"+createTime+"\nlastAccessTime:"+lastAccessTime);
}

Describing Table Information

You can call an API to obtain the metadata description of a table. The example code is as follows: 
private static void getTableDetail(Table table) throws DLIException { 
  // Call getTableDetail on the Table object to obtain table information.
  //  TableSchema tableSchema=table.getTableDetail();
  // Output
  System.out.println(List<Column> columns = tableSchema.getColumns());
  System.out.println(List<String> sortColumns = tableSchema.getSortColumns());
  System.out.println(String createTableSql = tableSchema.getCreateTableSql());
  System.out.println(String tableComment = tableSchema.getTableComment());
}
Parent topic: SDKs Related to SQL Jobs