User Tools

Site Tools


transformations:deletedbrowsbykeys

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

transformations:deletedbrowsbykeys [2017/05/03 03:00] (current)
dmitry created
Line 1: Line 1:
 +===== Delete matching database rows =====
  
 +Deletes rows in database table where a combination of key fields matches a combination of key fields in EasyMorph table. ​
 +
 +In alternative mode, deletes rows where a combination of key fields DOESN'​T MATCH any combination of key fields in EasyMorph table.
 +
 +Under the hood the transformation creates a temporary table in the target database, uploads key field combinations into it and performs DELETE..WHERE ..EXISTS statement. After the statement is executed the temporary table is deleted.
 +
 +The operation is //atomic//, meaning that it either successfully deletes all matching (or non-matching) rows, or doesn'​t delete anything if a failure occurs.
 +
 +**Use cases**
 +This transformation can be used for deleting records which IDs are obtained from another data source (e.g. text file or spreadsheet).
transformations/deletedbrowsbykeys.txt · Last modified: 2017/05/03 03:00 by dmitry