[[["わかりやすい","easyToUnderstand","thumb-up"],["問題の解決に役立った","solvedMyProblem","thumb-up"],["その他","otherUp","thumb-up"]],[["わかりにくい","hardToUnderstand","thumb-down"],["情報またはサンプルコードが不正確","incorrectInformationOrSampleCode","thumb-down"],["必要な情報 / サンプルがない","missingTheInformationSamplesINeed","thumb-down"],["翻訳に関する問題","translationIssue","thumb-down"],["その他","otherDown","thumb-down"]],["最終更新日 2025-09-05 UTC。"],[],[],null,["# Validate your data migration\n\nData validation is the process of comparing data from both the source and the\ndestination database tables to ensure they match.\n\nThe [Data Validation Tool (DVT)](https://pypi.org/project/google-pso-data-validator/#:%7E:text=The%20Data%20Validation%20Tool%20is,with%20multi%2Dleveled%20validation%20functions)\nis an open source tool that can connect to data stores and perform checks\nbetween your source database and Spanner. We recommend using it to perform\nbasic validations as a part of your migration, such as the following:\n\n- Check that all tables were created and that all schema mappings are correct.\n- Match the total number of rows for each table.\n- Extract random rows to verify consistency.\n- Validate your columns, for example, use `count`, `sum`, `avg`, `min`, `max`, or `group by`.\n- Compare any cyclic redundancy checks or hash functions at the row level.\n\nTo perform more specific validations, build custom checks during migration."]]