JMeter and JDBC

Apache JMeter can query databases directly using JDBC components rather than relying on CSV data sources. This approach is useful when test data is already in a database or when you need dynamic data during test execution.

JDBC Components

Two main components are required:

JDBC Connection Configuration - Establishes the database connection
JDBC Request - Executes queries against the database

JDBC Connection Configuration

This component establishes the database connection pool. Add it to your test plan before the JDBC Request sampler.

Key Configuration Fields

Field	Example Value	Description
Variable Name	MySQLDB	Name for the connection pool
Database URL	jdbc:mysql://localhost:3306/testdb	JDBC connection string
JDBC Driver class	com.mysql.jdbc.Driver	Database driver class
Username	testuser	Database username
Password	********	Database password

Common JDBC URLs

# MySQL
jdbc:mysql://hostname:3306/database

# PostgreSQL
jdbc:postgresql://hostname:5432/database

# Oracle
jdbc:oracle:thin:@hostname:1521:SID

# SQL Server
jdbc:sqlserver://hostname:1433;databaseName=database

JMeter creates a single persistent connection pool that can be reused throughout the test plan.

JDBC Request Sampler

The JDBC Request component queries the configured database.

Required Fields

Field	Value	Description
Variable Name of Pool	MySQLDB	Must match Connection Configuration
Query Type	Select Statement	Type of SQL operation
Variable names	count	Variable to store result
Result Variable name	Request_1	Name for the ResultSet
Handle ResultSet	Count Records	How to process results

Example Query

SELECT COUNT(*) FROM dummydata;

The count result is stored in the ${count} variable for subsequent test plan use.

Query Type Options

Eight query types are supported:

Query Type	Use Case
Select Statement	Read data
Update Statement	INSERT, UPDATE, DELETE operations
Callable Statement	Stored procedures
Prepared Select Statement	Parameterized SELECT
Prepared Update Statement	Parameterized INSERT/UPDATE/DELETE
Commit	Explicit commit
Rollback	Explicit rollback
AutoCommit(false)	Disable auto-commit
AutoCommit(true)	Enable auto-commit

Handle ResultSet Methods

Three approaches for processing results:

Count Records

Iterates through variables, storing values as strings. Each column becomes a variable:

${column1_1}, ${column1_2}, ${column1_3}...

Store as String

All variables stored as strings with column names:

${Result_1} contains the full result as a string

Store as Object

ResultSet variables stored as objects for manual iteration without automatic traversal. Useful when you need programmatic access:

// In BeanShell/JSR223
vars.getObject("Result_1")

Complete Example

Here’s a complete setup for reading user data:

Test Plan
  + JDBC Connection Configuration (MySQLDB)
  + Thread Group
    + JDBC Request
        Variable Name of Pool: MySQLDB
        Query Type: Select Statement
        Query: SELECT user_id, username FROM users LIMIT 100
        Variable names: user_id,username
        Result Variable name: Users
        Handle ResultSet: Count Records
    + HTTP Request
        Use ${user_id_1}, ${username_1} etc.

Driver Setup

Ensure the JDBC driver JAR is in JMeter’s lib folder:

# Copy driver to JMeter lib directory
cp mysql-connector-java-8.0.x.jar $JMETER_HOME/lib/