There are many reasons why the sync speed may slow down. The principal one is the presence of primary keys in synchronized tables. One more cause of deceleration is a quantity of records and fields. And finally, the third decisive reason that matters is data type. For example, if a record includes several empty fields, the speed of operation will be considerably faster in comparison with records containing binary data.
Three synchronization types (Insert, Update, Drop) are available. They can be used separately or together.
Update sync type estimates the similarity and the difference between records and then replaces modified records in a destination database with ones from source DB.
Drop and/or Insert types are intended for comparison of Missing and Additional records but these synchronization options make a comparison of Primary Keys' array, not every record
Read more information about Insert, Update, Drop and Mixed synchronization types
Choose the one of the following ways of solving the synchronization speed issue:
1. Activate triggers checking "Trigger-based sync" option at the Customization stage.
Trigger based synchronization works for the following databases in both directions:
- MS SQL & MySQL
- Oracle & MS SQL
- Oracle & MySQL
- Oracle & PostgreSQL
- Firebird & MS SQL
- Firebird & MySQL
- PostgreSQL & MSSQL
- PostgreSQL & MySQL
More information on how triggers work.
2. Use filters to specify only needed set of data for synchronization.
3. Select the tables that require more time to be synchronized and move them to separate session for synching.
4. If there are no Primary keys in database, please add them. Note that presence of Primary keys can be checked out at the Customization stage.
5. Please check synchronizing options in your session before starting scheduling.
NOTE: Take into account that keeping your databases in conformity, you should activate "Overwrite database" and "Overwrite table" options at the Customization step.