Import data from JSON to SQL Server via command line on Windows

Want to import data from JSON Lines (JSONL) to SQL Server via Command Line Interface (CLI) on Windows?

Using mssql-cmd, a Command Line Interface (CLI) client for SQL Server, you can import data from JSON Lines to SQL Server easily and fast. Direct Interaction or Scripting and Automation.

• No need to install SQL Server client library.
• Convenient to deploy to cloud. No need to run installation file, just uncompress and run, immediately.
• Commands are entered into a terminal or command prompt, accessed from local or remote (like SSH).
• Support Windows, Linux, and MacOS.

Download mssql-cmd Windows version
mssql-cmd.windows-386.zip
mssql-cmd.windows-amd64.zip

JSON Lines text format, also called newline-delimited JSON (NDJSON), or Line-delimited JSON (LDJSON). JSON Lines files may be saved with the file extension .jsonl, *.ndjson, *.ldjson.

Import data from JSON Lines to SQL Server via command line on Windows

1. In interactive mode:

mssql-cmd> load table=media_messages 
      > datafile=f:\media_messages.json 
      > filetype=json;

2. In batch mode:

mssql-cmd dsn="pan:withdata@192.168.0.102:3306/test" task=load table=media_messages datafile=f:\media_messages.json filetype=json quit=y

“loadtype=replace” will delete all data in table before inserting.

See parameters detail.

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More about mssql-cmd – Command Line Interface (CLI) tool for SQL Server

JSON → SQL Server reference

Type mapping

Value kind	in JSON	in SQL Server
Int	1234 (number)	int
Bigint	9007199254740993	bigint
Decimal	1234.56 (number)	decimal(p,s)
Float	1.234e10 (number)	float
Text	"text" (string)	nvarchar(n)
Long text	"multi-line\ntext" (escaped newline inside a string)	nvarchar(max)
Date	"2026-09-18" (string)	date
Datetime	"2026-09-18T14:30:00Z" (string)	datetime2
Binary	"base64:..." (string)	varbinary(max)
Boolean	true / false (boolean)	bit
JSON	nested object or array, kept as structure	nvarchar(max)

Dialect differences

JSON is a file format and SQL Server is a database server, so the target has to be told the types the file never carried - the rows below are where the two sides diverge.

Property	in JSON	in SQL Server
port	—	1433
identifiers	Double quotes; backslash escapes	[square brackets]
row limit	—	SELECT TOP n
dates	No date type: dates arrive as strings and the reader must p...	datetime, datetime2, date, time
long text	—	nvarchar(max)
binary	Not supported natively - base64 inside a string	varbinary(max)
separator	Braces and commas	—
encoding	UTF-8 by definition	—
typing	string, number, boolean, null, object, array - no date type	—
shape	Nested objects and arrays	Tables of rows and columns
ceiling	Whole document is usually parsed into memory	—

Command line

Side	Command
SQL Server	bcp
SQL Server (load)	bcp, or BULK INSERT

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