Convert JSON 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 dataT-SQL type
Whole numberBIGINT
Decimal (money)DECIMAL(10,2)
Floating pointFLOAT
True / falseBIT
DateDATE
Date and timeDATETIME2
Short textNVARCHAR(255)
Long textNVARCHAR(MAX)
Binary dataVARBINARY(MAX)

Working from a .json file

A .json file can be almost any shape, and only a few of those shapes are a table. What the reader accepts, and what it does with the rest, is the thing worth knowing before you upload one.

  • A wrapper is unwrapped only when the object has exactly one key and that key holds a list of objects. {"meta": {...}, "data": [...]} has two keys, so it is read as a single row instead.
  • An array of strings, or an array of arrays, is refused with "Expected a JSON array of objects" - there are no column names in it to build a table from.
  • Columns are the union of the keys seen in the first 10,000 records, in the order they first appear. A key that shows up only after that is not part of the table.

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 JSON

  • 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 JSON 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 JSON 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.

This conversion, under other names

Convert JSON to something else

Convert something else to T-SQL