Export PostgreSQL Database to JSON

Using row_to_json and json_agg Functions

To export a PostgreSQL database to JSON, first apply the row_to_json function to convert table rows into JSON objects. Then, aggregate these objects into a JSON array using the json_agg function. This ensures the output is a valid JSON array, complete with square brackets and comma-separated values.

Exporting with COPY Command

While the COPY command can be used to export data, it does not produce valid JSON by default, as it outputs each JSON object per line without proper array formatting. To circumvent this, wrap the results using a subquery with json_agg to maintain column names and ensure the output is a valid JSON array.

Converting to CSV and JSON Lines

For exporting a PostgreSQL table to a CSV file, use the psql utility with the COPY command. Then, you can convert the CSV file to JSON lines using spyql. This two-step process is helpful if you require the data in a line-delimited JSON format.

SQL Command for JSON Export

To directly export a query result to JSON format, use the SQL command SELECT ROW_TO_JSON(t, TRUE) FROM ( $sql ) t. This command converts each row of your query result into a JSON object.

Frequently Asked Questions

How do I export a PostgreSQL table to a JSON file?

Use the COPY command with the ROW_TO_JSON function to export a PostgreSQL table to a file, and wrap the query with json_agg to output valid JSON.

Why is the file output from the COPY command not valid JSON when exporting a PostgreSQL table?

The COPY command alone does not format the output as a single, valid JSON array; it requires functions like ROW_TO_JSON and json_agg to encapsulate the row outputs into a JSON array.

Can I create a valid JSON file from a PostgreSQL table using the COPY command?

Yes, by using the COPY command with functions like ROW_TO_JSON and json_agg, you can create a valid JSON file from a PostgreSQL table.

How do I ensure the JSON file exported from PostgreSQL is valid if I use the COPY command?

To ensure the JSON file is valid, use the COPY command in conjunction with the ROW_TO_JSON function and encapsulate the result with json_agg.

What is the purpose of the ROW_TO_JSON function in exporting a PostgreSQL table to JSON?

The ROW_TO_JSON function is used to convert each row of a PostgreSQL table into a JSON object, which is necessary for transforming table data into JSON format.

Common Use Cases

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  Migrating data from a PostgreSQL database to a NoSQL database that supports JSON format
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  Creating backups of PostgreSQL database tables in a human-readable JSON format
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  Facilitating data interchange between a PostgreSQL database and web applications using JSON
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  Enabling data analysis and visualization tools that require input in JSON format to process PostgreSQL data
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  Streamlining the process of updating remote databases with PostgreSQL data through JSON formatted files

Why Choose Sourcetable Over Traditional JSON Exports

Opt for Sourcetable to streamline data extraction from Postgres databases directly into a user-friendly spreadsheet interface. Eliminate the complexity of JSON exports.

Experience real-time data querying with Sourcetable's intuitive spreadsheet-like platform, ideal for agile data manipulation without the need for traditional database exports.

Sourcetable simplifies data consolidation, offering a singular hub for diverse data sources, enhancing productivity and decision-making efficiency.

Transform your data interaction with Sourcetable's seamless integration, bypassing the technical hurdles of exporting databases to JSON format.