resultSet

A result set is a set of results returned after the relational database (RDB) query APIs are called. You can use the resultset APIs to obtain required data.

NOTE

• The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.

• The APIs of this module are no longer maintained since API version 9. You are advised to use @ohos.data.relationalStore#ResultSet.

ResultSet

Provides methods to access the result set, which is obtained by querying the RDB store.

Usage

You need to obtain a resultSet object by using RdbStore.query().

import dataRdb from '@ohos.data.rdb';
let predicates = new dataRdb.RdbPredicates("EMPLOYEE");
predicates.equalTo("AGE", 18);
let promise = rdbStore.query(predicates, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
promise.then((resultSet) => {
    console.log(TAG + "resultSet columnNames:" + resultSet.columnNames);
    console.log(TAG + "resultSet columnCount:" + resultSet.columnCount);
});

Properties

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

getColumnIndex

getColumnIndex(columnName: string): number

Obtains the column index based on the column name.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  resultSet.goToFirstRow();
  const id = resultSet.getLong(resultSet.getColumnIndex("ID"));
  const name = resultSet.getString(resultSet.getColumnIndex("NAME"));
  const age = resultSet.getLong(resultSet.getColumnIndex("AGE"));
  const salary = resultSet.getDouble(resultSet.getColumnIndex("SALARY"));

getColumnName

getColumnName(columnIndex: number): string

Obtains the column name based on the column index.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const id = resultSet.getColumnName(0);
  const name = resultSet.getColumnName(1);
  const age = resultSet.getColumnName(2);

goTo

goTo(offset:number): boolean

Moves the cursor to the row based on the specified offset.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  let predicatesgoto = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoto = rdbStore.query(predicatesgoto, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoto.then((resultSet) => {
      resultSet.goTo(1);
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToRow

goToRow(position: number): boolean

Moves the cursor to the specified row in the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  let predicatesgotorow = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygotorow = rdbStore.query(predicatesgotorow, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygotorow.then((resultSet) => {
      resultSet.goToRow(5);
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToFirstRow

goToFirstRow(): boolean

Moves the cursor to the first row of the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoFirst = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoFirst = rdbStore.query(predicatesgoFirst, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoFirst.then((resultSet) => {
      resultSet.goToFirstRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToLastRow

goToLastRow(): boolean

Moves the cursor to the last row of the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoLast = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoLast = rdbStore.query(predicatesgoLast, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoLast.then((resultSet) => {
      resultSet.goToLastRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToNextRow

goToNextRow(): boolean

Moves the cursor to the next row in the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoNext = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoNext = rdbStore.query(predicatesgoNext, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoNext.then((resultSet) => {
      resultSet.goToNextRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToPreviousRow

goToPreviousRow(): boolean

Moves the cursor to the previous row in the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoPrev = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoPrev = rdbStore.query(predicatesgoPrev, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoPrev.then((resultSet) => {
      resultSet.goToPreviousRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

getBlob

getBlob(columnIndex: number): Uint8Array

Obtains the value in the specified column in the current row as a byte array.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const codes = resultSet.getBlob(resultSet.getColumnIndex("CODES"));

getString

getString(columnIndex: number): string

Obtains the value in the specified column in the current row as a string.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const name = resultSet.getString(resultSet.getColumnIndex("NAME"));

getLong

getLong(columnIndex: number): number

Obtains the value in the specified column in the current row as a Long integer.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const age = resultSet.getLong(resultSet.getColumnIndex("AGE"));

getDouble

getDouble(columnIndex: number): number

Obtains the value in the specified column in the current row as a double.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const salary = resultSet.getDouble(resultSet.getColumnIndex("SALARY"));

isColumnNull

isColumnNull(columnIndex: number): boolean

Checks whether the value in the specified column of the current row is null.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const isColumnNull = resultSet.isColumnNull(resultSet.getColumnIndex("CODES"));

close

close(): void

Closes this result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Example

  let predicatesClose = new dataRdb.RdbPredicates("EMPLOYEE");
  let promiseClose = rdbStore.query(predicatesClose, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promiseClose.then((resultSet) => {
      resultSet.close();
  }).catch((err) => {
      console.log('resultset close failed');
  });

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