Eugen Barilyuk

Published: 07 May 2025

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SQLite to CSV / Excel XLSX Converter
CSV / Excel XLSX to SQLite Converter

SQLite to CSV/XLSX CSV/XLSX to SQLite

Step 1: Upload SQLite Database

Drag & drop your SQLite database file here or click to browse

Step 2: Select Table

Loading tables...

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Step 3: Export Data

Export as CSV Export as XLSX

Step 1: Upload CSV or XLSX File

Drag & drop your CSV or XLSX file here or click to browse

Step 2: Preview and Configure

Table Name:

Column Types:

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Step 3: Create SQLite Database

Database File Name:

.sqlite

Create SQLite Database

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SQLite to CSV/XLSX Conversion technical details

The conversion process is executed entirely within the user's browser using JavaScript and WebAssembly, without relying on server-side operations. Below is a step-by-step breakdown of how the SQLite file is processed and transformed into CSV or Excel (XLSX):

1. Loading External Libraries

Upon accessing the tool, key JavaScript libraries are loaded:

• sql-wasm.js: Enables WebAssembly-powered SQLite querying within the browser. This library uses SQLite compiled to WebAssembly, allowing SQL queries to be run directly in the browser without any server dependencies.
• xlsx.full.min.js: Facilitates the creation and manipulation of Excel spreadsheets. It supports creating workbooks, defining worksheets, and exporting binary XLSX files compatible with Microsoft Excel.
• PapaParse.min.js: Handles parsing and exporting structured CSV data. It efficiently serializes JavaScript arrays and objects into properly escaped, comma-separated text for download.

2. SQLite Database File Processing

When a user uploads an SQLite file, the following sequence occurs:

• The file is loaded into memory using JavaScript's File API. This allows reading the binary contents of the SQLite database asynchronously and without page reloads.
• sql-wasm.js initializes an in-memory SQLite database and reads the binary contents. The contents are passed to the library as an ArrayBuffer or Uint8Array, which is then interpreted as a full SQLite database.
• The database structure (tables, columns, and rows) is queried using standard SQL commands. These commands are issued through the in-browser SQL interface, allowing interactive data inspection and extraction.

3. Data Extraction

Once the SQLite database is loaded, the tool performs the following operations:

• Executes a query to fetch the required table contents. This typically uses a command like SELECT * FROM table_name to gather all available data.
• Retrieves column headers dynamically to ensure proper structuring. The result set includes metadata about column names, which is essential for generating CSV headers or Excel sheet labels.
• Extracts row-by-row data and stores it in a JavaScript array for further manipulation. Each row is parsed into a nested array or object format suitable for downstream formatting into CSV or XLSX.

4a. CSV Generation (Using PapaParse)

If the user selects CSV as the export format:

• The extracted table data is passed to PapaParse. The library is given a two-dimensional array where the first row contains headers and subsequent rows contain values.
• PapaParse serializes the data into a well-structured CSV format. It ensures special characters, quotes, and delimiters are properly escaped and formatted.
• A downloadable CSV file is generated using a Blob object and linked to the browser's download function. The Blob contains the raw text content, and a temporary anchor tag is used to trigger the file save dialog.

4b. Excel (XLSX) Generation (Using xlsx.js)

If the user selects Excel as the export format:

• The extracted data is converted into a worksheet using XLSX.utils.aoa_to_sheet. This function transforms a 2D array (array of arrays) into a format compatible with Excel cells, including rows, columns, and cell types.
• A new workbook is created using XLSX.utils.book_new and populated with the worksheet. The sheet is added to the workbook under a specific name using XLSX.utils.book_append_sheet.
• The workbook is serialized into an XLSX binary format. The XLSX.write method is used with appropriate options to generate a base64 or binary-encoded Blob suitable for download.
• A downloadable XLSX file is created and provided via the browser. As with CSV, the file is wrapped in a Blob and linked to an a tag for user-initiated download.

5. Downloading the Converted File

Once conversion is complete, the tool generates a direct download link:

• The file is stored in a Blob object. The Blob holds either plain CSV text or binary XLSX content, depending on the selected export format.
• A temporary link is created using URL.createObjectURL(blob). This method generates a temporary URL that points to the in-memory Blob, which the browser can access like a real file.
• The user clicks the generated link to download the file locally. The link's download attribute specifies the filename and file extension, ensuring correct file type recognition by the system.

CSV/XLSX to SQLite Conversion

The reverse conversion (importing data into SQLite) follows these steps:

1. Loads and parses the input file (CSV using PapaParse or Excel using SheetJS).
2. Extracts headers and data rows from the parsed content.
3. Infers appropriate SQLite data types (TEXT, INTEGER, REAL) for each column based on sample data.
4. Creates a new in-memory SQLite database using sql-wasm.js.
5. Generates and executes CREATE TABLE SQL statements with user-defined or inferred column types.
6. Batches and executes INSERT statements to populate the table with data.
7. Exports the complete database as a binary SQLite file for download.