Oracle → PostgreSQL

Complete Oracle to PostgreSQL Migration

A full, automated pipeline from schema discovery through PL/SQL conversion, parallel bulk copy, row-level validation, and CDC-based zero-downtime cutover. No manual DDL scripts. No guesswork.

99.7%

Schema conversion accuracy

87,000

Rows/sec throughput

3 weeks

Avg migration time

Data loss incidents

How It Works

Connect

Enter your Oracle credentials (host, port, service name, user). DBMigrateAIPro scans all accessible schemas, tables, indexes, sequences, packages, procedures, functions, and triggers — no manual inventory required.

Assess

Receive a risk report covering: XMLTYPE columns, partitioned tables, circular foreign key chains, sequence dependencies, unsupported Oracle-specific types (RAW, BFILE, INTERVAL), and PL/SQL constructs that require manual review.

Migrate

Parallel bulk copy streams data with FK and trigger deferral enabled. Sequences are auto-synced to the max row value plus a configurable buffer. Large LOB columns are streamed in chunks to avoid memory pressure.

Validate

Row-count and MD5 checksum comparison report per table. Once validated, flip to CDC mode using Oracle LogMiner to tail remaining changes until cutover lag drops below your configured threshold (default: 500ms).

What Gets Converted

Schema Objects

✓Tables
✓Views
✓Indexes (B-tree, function-based)
✓Primary keys
✓Foreign keys
✓Check constraints
✓Unique constraints
✓Sequences
✓Synonyms
✓Column and table comments

Code Objects

✓Stored procedures
✓Functions
✓Packages → schema-namespaced functions
✓Triggers (row-level)
✓Type definitions (object types)

Code objects with unsupported constructs are flagged in the assessment report with line-level annotations and suggested rewrites.

PL/SQL → PL/pgSQL Conversion

DBMigrateAIPro transpiles Oracle PL/SQL to PostgreSQL PL/pgSQL automatically, handling the most common idioms. Complex logic is flagged for human review.

Oracle PL/SQL (before)

CREATE OR REPLACE FUNCTION get_emp_salary(
  p_emp_id IN NUMBER
) RETURN NUMBER IS
  v_salary NUMBER;
BEGIN
  SELECT NVL(salary, 0)
    INTO v_salary
    FROM employees
   WHERE ROWNUM = 1
     AND hire_date < SYSDATE - 365
     AND emp_id = p_emp_id;

  RETURN v_salary;
EXCEPTION
  WHEN NO_DATA_FOUND THEN
    RETURN 0;
END;

PostgreSQL PL/pgSQL (after)

CREATE OR REPLACE FUNCTION get_emp_salary(
  p_emp_id NUMERIC
) RETURNS NUMERIC AS $$
DECLARE
  v_salary NUMERIC;
BEGIN
  SELECT COALESCE(salary, 0)
    INTO v_salary
    FROM employees
   WHERE hire_date < NOW() - INTERVAL '365 days'
     AND emp_id = p_emp_id
   LIMIT 1;

  RETURN COALESCE(v_salary, 0);
EXCEPTION
  WHEN NO_DATA_FOUND THEN
    RETURN 0;
END;
$$ LANGUAGE plpgsql;

Key transformations: ROWNUM = 1 → LIMIT 1 · NVL() → COALESCE() · SYSDATE → NOW() · NUMBER → NUMERIC · IS RETURN → RETURNS … AS $$ … $$ LANGUAGE plpgsql

Common Gotchas

These are the issues that sink Oracle migrations. DBMigrateAIPro flags all of them during assessment.

XMLTYPE

Oracle XMLTYPE has no direct PostgreSQL equivalent. DBMigrateAIPro maps it to JSONB when the content is structured, or TEXT for raw XML. Queries using XMLQUERY / XMLTABLE require manual rewrite.

CONNECT BY

Hierarchical queries using CONNECT BY PRIOR have no direct syntax in PostgreSQL. These are automatically converted to recursive CTEs (WITH RECURSIVE … UNION ALL). Complex NOCYCLE clauses need manual validation.

Oracle Packages

PostgreSQL has no package construct. All package procedures and functions are flattened into a dedicated schema named after the package (e.g., pkg_orders.get_total). Package-level global variables require session-local workarounds.

NUMBER Type

Oracle NUMBER with no precision maps to NUMERIC in PostgreSQL, which is exact but slower than FLOAT8. For integer-only columns, DBMigrateAIPro selects INT or BIGINT based on the observed max value during assessment.

Oracle DATE Includes Time

Oracle DATE stores both date and time components. PostgreSQL DATE stores date only. All Oracle DATE columns are mapped to TIMESTAMP to avoid silent data truncation.

ROWID

Oracle ROWID is a physical row address with no PostgreSQL equivalent. PostgreSQL ctid is similar but can change on VACUUM. Any application logic relying on ROWID for pagination or update targeting must be rewritten.

Prerequisites

→Oracle 11g Release 2 or later (12c, 19c, 21c fully tested)
→Supplemental logging enabled: ALTER DATABASE ADD SUPPLEMENTAL LOG DATA
→SELECT on DBA_LOGMNR_CONTENTS granted to the migration user
→EXECUTE privilege on DBMS_LOGMNR and DBMS_LOGMNR_D
→oracledb Python package (thin mode supported — no Oracle Client install needed)
→Network access from the DBMigrateAIPro agent host to Oracle listener port (default 1521)

Start your Oracle migration today

Read the full technical guide or explore pricing. Most teams complete a proof-of-concept migration in under two hours.

Read the docs View pricing