Convert Microsoft Access to Oracle
Upload a .mdb or .accdb or .mde file and get back a Oracle SQL script you can load straight into your database. Types are preserved rather than flattened to text. Free, no registration, up to 10MB.
Click to upload or drag and drop
CSV, Excel, SQLite, SQL, DBF (max 10 MB)
How your data is typed in Oracle
Generated from the converter's own Oracle type mapping — this is what it actually emits, not an example.
| Your data | Oracle type |
|---|---|
| Whole number | NUMBER(19) |
| Decimal (money) | NUMBER(10,2) |
| Floating point | BINARY_DOUBLE |
| True / false | NUMBER(1) |
| Date | DATE |
| Date and time | TIMESTAMP |
| Short text | VARCHAR2(255) |
| Long text | CLOB |
| Binary data | BLOB |
Working from a Microsoft Access database
The reason people search for this one is usually not the file, it is the software. Converting here needs no copy of Microsoft Access, no Office licence and no Windows machine anywhere in the process.
- →Reading happens on the server through the mdbtools utilities, so the ACE and Jet ODBC drivers are never involved: no "provider is not registered on the local machine", and no 32-bit versus 64-bit driver mismatch.
- →You do not need Access at your end to check the result either. The preview lists the tables, columns and detected types before you download anything.
- →Nothing is installed or run on your own machine, and the server's temporary copy of your database is deleted as soon as the download has been sent.
Oracle-specific edges in the script
Oracle diverges further from ordinary SQL than any other target here, and the script is shaped around that. Three of its choices are worth reading before you load, because each is a place where the source can hold something Oracle has no room for.
- →Oracle's reserved list is full of words that legacy tables use as column names, so those get a trailing underscore: a column called DATE becomes DATE_, NUMBER becomes NUMBER_, LEVEL becomes LEVEL_.
- →Binary values are written as HEXTORAW('...'), which a plain SQL script can carry only up to 2000 hex characters - 1000 bytes. Anything larger needs PL/SQL chunking that no portable script can express, so a table of real attachments moves better through the SQLite or DuckDB target.
- →A string column of unknown length is declared VARCHAR2(4000) and anything longer becomes a CLOB. Under the default settings VARCHAR2 counts bytes rather than characters, so 4000 characters of Cyrillic or CJK will not fit in one.
- →Rows are batched a hundred to a statement, each block closed off with SELECT 1 FROM DUAL, so a 100,000-row table arrives as a thousand statements rather than a hundred thousand.
Reading Microsoft Access
- →Dates are exported in ISO form, avoiding the ambiguous 12/02/21 that Access tools produce by default.
- →NULL and the empty string stay distinct.
- →Access can hold dates outside the range it can represent. Those become NULL and the conversion tells you, rather than dropping them silently.
- →Requires mdbtools on the server; if it is unavailable you get a clear error rather than a partial conversion.
Writing Oracle
- →Uses INSERT ALL rather than multi-row VALUES, which Oracle rejects outright — the most common reason a generated Oracle script fails to load.
- →Dates are written with TO_DATE and an explicit format mask.
- →Booleans become NUMBER(1), because Oracle had no BOOLEAN column type before 23c.
- →Identifiers are capped at 30 characters so the script loads on Oracle 12.1 and earlier too.
- →Note that Oracle itself treats an empty string as NULL — that is Oracle behaviour, not a conversion error.
What you get
A ZIP containing dump.sql, plus a README with the exact command to load it. If anything about your data needed a judgement call, a _warnings.txt explains it.
Load this dump into Oracle:
sqlplus USER/PASSWORD@//HOST:1521/SERVICE @dump.sql
Notes specific to Oracle:
- Oracle treats an empty string as NULL. A column that held ''
in the source will read back as NULL here. This is Oracle
behaviour, not a conversion error, and it cannot be avoided.
- Booleans are NUMBER(1), 1 or 0: Oracle had no BOOLEAN column
type before 23c.
- Identifiers are capped at 30 characters for compatibility
with 12.1 and earlier.
- Table and column names are quoted, so Oracle keeps their exact
case. Unquoted Oracle identifiers fold to upper case, which
means you must quote them in your queries too:
SELECT * FROM "MyTable"; not SELECT * FROM MyTable;Questions
- Is converting Microsoft Access to Oracle free?
- Yes. Files up to 10MB convert free with no account. There is a limit of five conversions per day per IP address.
- Will my Microsoft Access data keep its types in Oracle?
- Yes — that is the point. Whole numbers, decimals, dates and booleans are mapped to real Oracle types rather than everything becoming text. The mapping table above shows exactly what you get.
- Do you store my file?
- No. The file is written to a temporary directory, converted, and the directory is deleted as soon as your download has been sent.