Which Tool Best Migrates SQL Server to MySQL? A Detailed Performance Comparison

Background and Goal

The migration required moving a client‑server product built on SQL Server to a MySQL cloud service on Alibaba Cloud. Because dozens of customers would upgrade, the migration had to be 100% accurate and as fast as possible.

Test Environment

Source database: MesoftReportCenter on SQL Server (Windows XP, 2 GB RAM, 100 Mbps). Target database: MySQL on a separate VM (Windows XP, 1 GB RAM, 100 Mbps). Two largest tables – HISOPChargeIntermediateResult and HISOPChargeItemIntermediateResult – were selected, containing about 3.28 million rows.

Tools Evaluated

SQLyog – https://www.webyog.com/product/sqlyog

Navicat Premium – https://www.navicat.com/products/navicat-premium

Mss2sql – http://www.convert-in.com/

DB2DB – http://www.szmesoft.com/DB2DB

Evaluation Criteria

Software usability (configuration ease)

Processing speed and memory consumption

Data integrity after migration

Trial‑version restrictions

Other functional features

Usability Assessment

All tools required configuring a source connection. SQLyog used an old ODBC driver, which many modern developers find unfamiliar and required the appropriate driver to be installed locally. Navicat Premium also relied on an ADO‑style connection and presented a non‑intuitive UI where adding a new connection required clicking a tiny hidden button; the connection settings were not saved between runs. Mss2sql offered a wizard‑style interface that was easy to follow, with many adjustable options. DB2DB, developed locally, displayed a fully Chinese UI and a straightforward “one‑click” workflow, similar to Mss2sql.

Speed and Memory Test

The tests covered two scenarios: migrating to a local MySQL instance for code testing, and migrating to a cloud MySQL instance for production use. Each tool processed roughly 3.28 million rows.

DB2DB completed the migration in 2 minutes 44 seconds, the fastest of all.

Mss2sql took about 726 seconds (≈12 minutes) and showed relatively high CPU usage but remained acceptable.

Navicat Premium exhibited medium speed; however, its CPU and memory usage were high, and it struggled with the SQL Server Money type, requiring manual schema adjustments.

SQLyog was the slowest, taking the longest time while maintaining low CPU usage.

Data Integrity Test

All four tools transferred the full row count. However, database size differences revealed that Navicat Premium did not create indexes or primary keys for the migrated tables, resulting in a significantly smaller database file. Default‑value handling varied:

SQLyog: fully supports SQL Server default values.

Navicat Premium: does not support default values at all.

Mss2sql: supports defaults but contains a critical bug—empty string defaults become two consecutive single quotes (''), which can corrupt production data.

DB2DB: fully supports default values.

All tools correctly migrated Text and Image (binary) columns.

Other Features and Trial‑Version Limits

SQLyog and Navicat Premium provide extra management functions, making them more expensive. Navicat requires the Premium edition for migration. Mss2sql’s trial version limits processing to 50 seconds, rendering it impractical for large datasets. DB2DB’s trial caps at 100 000 records, targeting small‑scale projects.

Conclusion

DB2DB – best overall performance, free for the tested data volume, Chinese UI, and solid data integrity.

SQLyog – good data integrity but very slow for large tables.

Mss2sql – acceptable speed but suffers from a serious default‑value bug.

Navicat Premium – not recommended due to missing indexes/primary keys and poor default‑value handling.