SQL Select

Runs a SELECT query against a database and replaces the message with the rows returned. Each row is represented as a JSON object with column names as keys.

Field	Type	Default	Description
Driver	string	—	Database driver (required)
DSN	string	—	Connection string for the target database (required)
Table	string	—	The table to query (required)
Columns	array	—	A list of column names to select (required)
Where	string	—	An optional WHERE clause. Placeholder arguments are populated with Args Mapping
Args Mapping	Bloblang	—	Maps message fields to WHERE clause placeholder arguments
Prefix	string	—	An optional prefix to prepend before SELECT
Suffix	string	—	An optional suffix to append to the query
Init Statement	string	—	SQL statement to execute on the first connection
Conn Max Idle Time	string	—	Maximum idle duration before a connection is closed
Conn Max Life Time	string	—	Maximum total lifetime of a connection
Conn Max Idle	integer	2	Maximum number of idle connections in the pool
Conn Max Open	integer	0	Maximum number of open connections (0 = unlimited)

Supported drivers: mysql, postgres, clickhouse, mssql, sqlite, oracle, snowflake, trino, gocosmos, spanner.

Result Format

The message payload is replaced with an array of objects, where each object represents a row and column names are used as keys. If the query returns no rows, the message is replaced with an empty array.

Filtering with Where

Use the Where field to filter rows. Placeholder arguments in the WHERE clause are populated from the Args Mapping field. The placeholder style depends on the driver (e.g., ? for MySQL, $1 for PostgreSQL).

tip

Use Prefix and Suffix to add clauses like DISTINCT (prefix) or ORDER BY, LIMIT (suffix) to the generated SELECT query.