Step Type: Migrate Records

The Migrate Records step is the primary step type in Precision Bridge. It extracts records from a source table, transforms them using field mappings, and loads them into a target table.

Migrate Records is the most important step type in Precision Bridge. For comprehensive documentation covering every aspect of configuration, see the dedicated Migrate Records section.

If you're familiar with previous Precision Bridge versions, this step is the equivalent of a "Form Mapping."

Quick Reference

Tables Tab

Source connection and source table -- where records are extracted from
Target connection and target table -- where records are loaded into

See Configuring Tables for details.

Filter Tab

Query filter -- limits which records are extracted from the source table
Supports standard filter expressions, native queries, and formula-based filter values

See Configuring the Filter and the Filtering category for the full filter language reference.

Fields Tab

Configure how each target field is populated. Supported mapping types:

Type	Description
Constant	A fixed value for every record
Source Field	Direct mapping from a source field
Procedure Variable	Current value of a procedure variable
Mapping Variable	Value of an intermediate mapping variable
Formula	A computed expression using fields, variables, and functions
Match	Value translation for choice fields
Lookup	Value retrieval from related records in other tables
ID	Record ID translation using table correlations

See the Field Mappings articles for mapping type details, and Configuring Field Mappings for a walkthrough of the Fields tab.

Key Mappings

Key fields identify whether a target record already exists. When a key match is found, Precision Bridge can be configured to:

Update the existing record
Skip the record
Raise an error

If no match is found, a new record is inserted. See Key Mappings and Duplicate Handling for details.

Lookups Tab

Define lookup configurations for retrieving values from related tables. See Configuring Lookups.

Output Tab

Configure output variables to capture information after execution (e.g., ID maps, record counts). Enable table correlations to track source-to-target ID relationships. See Output and Correlations.

Preview Tab

Run a read-only dry-run of the step against a sample of source records (up to 100). The same transformation, lookup, key-match, and validation logic as real execution runs, but nothing is written to the target. Use preview to verify field mappings and filter logic before committing to a full migration. See Previewing a Migration.

Advanced Features

Mapping Variables — Intermediate calculated fields not written to the target, reusable across mappings
Validation Rules — Custom rules to validate records before insert/update, with configurable failure actions (skip, warning, error)
Attachment Migration — Optionally migrate file attachments associated with source records
Batch Sizing — Control the number of records sent per batch operation
Keyset Pagination — Reliable extraction of large datasets using keyset-based paging
Sampling Validation — Re-query a random sample of migrated records to verify accuracy after the migration completes
Per-Chunk Scripts — Run a user-authored Python script over each chunk of records, either before the upsert (with mutations written back to the target) or after the upsert (for observation and artifact generation)

See Advanced Options for full documentation on each feature.