Convert JSONL to T-SQL
Upload a .json or .ndjson file and get back a T-SQL 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 T-SQL
Generated from the converter's own T-SQL type mapping — this is what it actually emits, not an example.
| Your data | T-SQL type |
|---|---|
| Whole number | BIGINT |
| Decimal (money) | DECIMAL(10,2) |
| Floating point | FLOAT |
| True / false | BIT |
| Date | DATE |
| Date and time | DATETIME2 |
| Short text | NVARCHAR(255) |
| Long text | NVARCHAR(MAX) |
| Binary data | VARBINARY(MAX) |
Working from a .jsonl file
JSON Lines and NDJSON are the same format under two names, and .jsonl is the spelling used by jq pipelines, Spark and machine-learning tooling. The content converts identically; only the file name causes trouble.
- →The .jsonl extension is not one the uploader recognises. Rename the file to .ndjson or .json - nothing inside it has to change.
- →Tools that write JSON Lines usually emit a directory of shards, part-00000.jsonl and so on. Only one convertible file per upload is accepted, and with no enclosing array to merge, cat part-*.jsonl > all.ndjson is the whole job.
- →Relaxed JSON is not JSON: trailing commas, single quotes and unquoted keys fail to parse, which is what a file written in a JSON5-ish mode will do. Running it through jq normalises it.
The T-SQL the script actually uses
T-SQL is the language rather than the product, and it is exactly where a generic ANSI SQL script fails against SQL Server. Two of those differences are why this target has a dialect of its own instead of reusing the shared one.
- →Date and timestamp values are written as ordinary quoted strings. The ANSI typed literal - the word DATE in front of a quoted date - is not T-SQL, and the server rejects it, which on its own is enough to make a portable script fail to load.
- →GO is not a statement in the language at all. sqlcmd, SSMS and Azure Data Studio read it as a batch separator and the server never sees it, so a driver handed the whole file as one string chokes on it: run the file through one of those clients, or split the text on its GO lines and send the pieces in order down the same connection.
- →Rows are written 500 to a statement, comfortably under the 1000-row ceiling T-SQL puts on a single VALUES list. That ceiling is what makes a script built around one statement per table fail on any table worth converting.
Reading JSONL
- →JSON types are trusted: 1 and "1" stay different things.
- →Numbers with a decimal point are read as exact decimals rather than floats.
- →Both an array of objects and newline-delimited JSON work, and a wrapped array like {"data": [...]} is unwrapped automatically.
- →Nested objects are kept as JSON rather than flattened into invented column names.
Writing T-SQL
- →String literals carry the N prefix, so non-ASCII text survives whatever collation the database uses.
- →Timestamps become DATETIME2. T-SQL’s TIMESTAMP is a row-version counter, not a point in time.
- →Identity columns are wrapped in SET IDENTITY_INSERT so explicit key values load.
- →Statements are separated with GO in batches.
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 SQL Server:
sqlcmd -S HOST -U USER -P PASSWORD -d DATABASE -i dump.sql
Notes:
- Text columns are NVARCHAR and literals carry the N prefix, so
non-ASCII data survives regardless of database collation.
- Timestamps are DATETIME2. T-SQL's TIMESTAMP type is a row
version, not a point in time.Questions
- Is converting JSONL to T-SQL 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 JSONL data keep its types in T-SQL?
- Yes — that is the point. Whole numbers, decimals, dates and booleans are mapped to real T-SQL 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.