JDBC Driver
This article describes the JDBC driver provided by Exasol to connect third party applications to Exasol.
System requirements
JRE requirement
The JDBC driver requires a Java runtime environment. You can use the driver on any platform with JRE version 1.8.0_282 or later.
Tested systems
The driver has been tested on the following systems using the specified Java version with the latest available updates.
Windows (64-bit)
-
Windows 10
-
Windows Server 2016
-
Windows Server 2019
The JDBC driver is tested on Windows platforms for
Linux (64-bit)
-
Red Hat / CentOS 7
-
Red Hat / CentOS 8 Stream
-
OpenSUSE Leap 15.2
-
Debian 10
-
Ubuntu 18.04 LTS
-
Ubuntu 20.04 LTS
The JDBC driver is tested on Linux platforms for
macOS (64-bit)
-
macOS Catalina (10.15)
-
macOS Big Sur (11.6.1)
-
macOS Monterey (12.0.1)
The JDBC driver is tested on Mac OS for
FreeBSD (64-bit)
The JDBC driver is tested on FreeBSD 12.2 for OpenJDK
Download JDBC driver
-
Download the latest driver for your operating system from the Exasol Download Portal.
-
Run the downloaded executable file and follow the setup wizard to complete the installation.
Install JDBC driver
On Windows
The driver is installed as a .jar
archive in the installation directory.
On Linux/Unix
The driver is included in the download. Depending on the application, the archive must be added to the search path for the Java classes (CLASSPATH
).
All classes of the JDBC driver belong to the Java com.exasol.jdbc
package. The main class of the driver is com.exasol.jdbc.EXADriver
License
Each driver package includes the latest version of the license for the driver. The license allows you to bundle the driver with third-party software, for example when creating plugins for a BI tool. For more details, refer to the license file which is located in the folder where the driver was installed.
Integrate JDBC driver using Maven
The JDBC driver is also available on Maven Central (https://search.maven.org/artifact/com.exasol/exasol-jdbc). Add the following dependency to the build configuration of your project (for example, pom.xml
for Maven).
Replace the version number in this example with the latest supported driver version.
Exasol URL
The following URL structures are supported for the JDBC driver in Exasol.
Single host:
jdbc:exa:<host>[/<fingerprint>]:<port>[;<prop_1>=<value_1>]...[;<prop_n>=<value_n>]
Multiple hosts:
jdbc:exa:<host_1>[/<fingerprint>]:<port_1>[,<host_2>]...[,<host_n>:<port_n>][;<prop_1>=<value_1>]...[;<prop_n>=<value_n>]
The following list explains the elements of the URL structure.
-
jdbc:exa
-
This is a necessary prefix for the driver manager.
-
<host>/<fingerprint>:<port>
-
Defines the servers and the port of the Exasol cluster.
Servers can be specified as a single hostname or IP address, as multiple hostnames or IP addresses specified as a range using the format
first_host..last_host:port
, or as a comma-separated list of host:port pairs. When opening a connection, the driver will randomly choose an address from the specified range. If the connection fails, the driver will continue to try all other possible addresses in the range.If you cannot use TLS and you trust the server, you can include the server fingerprint in the URL.
Examples:
jdbc:exa:myhost/72975B4D331DEEB44FA41FB858A5417E163151BBFB45376574706800A8DCCE30:8563
jdbc:exa:myhost/72975B4D331DEEB44FA41FB858A5417E163151BBFB45376574706800A8DCCE30:8563,myhost2:8564
jdbc:exa:myhost1..4/72975B4D331DEEB44FA41FB858A5417E163151BBFB45376574706800A8DCCE30:8563
jdbc:exa:192.168.6.11..14/72975B4D331DEEB44FA41FB858A5417E163151BBFB45376574706800A8DCCE30:8563
You can also specify a file that contains a list of server definitions, for example:
//c:\mycluster.txt
. The two forward slashes indicate that the parameter value is a file path. -
<prop_i=value_i>
-
The port can be followed by an optional semicolon-separated list of properties that should be set during login. These properties correspond with the supported driver properties that are described in the following section.
The values of properties within the URL can only consist of alphanumeric characters.
Example from a Java program
import java.sql.*;
import com.exasol.jdbc.*;
public class jdbcsample
{
public static void main(String[] args)
{
try { Class.forName("com.exasol.jdbc.EXADriver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
Connection con=null;
Statement stmt=null;
try {
con = DriverManager.getConnection(
"jdbc:exa:192.168.6.11..14:8563;schema=SYS",
"sys",
"exasol"
);
stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM CAT");
System.out.println("Schema SYS contains:");
while(rs.next())
{
String str1 = rs.getString("TABLE_NAME");
String str2 = rs.getString("TABLE_TYPE");
System.out.println(str1 + ", " + str2);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {stmt.close();} catch (Exception e) {e.printStackTrace();}
try {con.close();} catch (Exception e) {e.printStackTrace();}
}
}
}
The code sample above builds a JDBC connection to an Exasol database on servers in IP address range 192.168.6.11
to 192.168.6.14
using port 8563
. User sys
with the password exasol
is logged in, and the schema sys
is opened. After that, all tables in this schema are shown.
Supported interfaces
Exasol provides the following interfaces:
-
EXADataSource
-
EXASocketFactory
EXADataSource
The JDBC driver provides a CommonDataSource interface called EXADataSource. Use EXADataSource to pass arguments using the setProperty()
method. For example:
EXADataSource ds = new EXADataSource();
ds.setProperty("socketfactory", "myTool.MySocketFactory");
ds.setProperty("<User>", "<MyDBUser");
...
EXASocketFactory
The JDBC driver provides a SocketFactory interface called EXASocketFactory. With EXASocketFactory you can use the Exasol specific method createCustomSocket
to connect with a set timeout for the connection. For example:
public abstract class EXASocketFactory extends SocketFactory {
public abstract Socket createCustomSocket(<InetAddressHost>, <Port>, <Timeout>) throws IOException;
When more than one host is specified in a connection string, the connect attempts to each of these hosts are made using the SocketFactory specified by the user and the timeout (if given) until one host is connected.
Supported driver standards
The JDBC driver supports JDBC 4.2 Core API. Detailed information about the supported interfaces are provided in the API Reference which you can find in the html
folder of the driver installation directory. If you want to learn more about JDBC, see JDBC Basics.
The standard includes the following:
- Access to the driver through the
DriverManager
API and configuration of the driver using theDriverPropertyInfo
interface. - Direct execution of SQL statements as a prepared statement and in batch mode.
- Support of more than one open
ResultSet
. - Support of the
DatabaseMetaData
andResultSetMetaData
metadata APIs.
The following features are not supported:
- Savepoints
- User-defined data types and the types
Blob
,Clob
,Array
, andRef
. - Stored procedures
- Read-only connections
- The API
ParameterMetaData
If the rowcount
of a query exceeds 2147483647 (231-1), the JDBC driver will return the value 2147483647. This is because of the 32-bit limitation for this return value defined by the JDBC standard.
Supported driver properties
The following table describes all properties that can be transferred to the JDBC driver through the URL. Properties that are not listed in the table are not supported in this version of Exasol.
The driver property names are case sensitive.
TLS encryption is required by default for all connections. The legacy ChaCha encryption method is deprecated and is not recommended. Connections from drivers that disable encryption through the encryption
property or switch to ChaCha encryption through the legacyencryption
property are not accepted in Exasol 8.19.0 or later.
If TLS encryption cannot be used and you trust the server, you can include the server fingerprint in the connection string to bypass TLS validation. For more information, see fingerprint.
Property | Value type | Description |
---|---|---|
authmethod
|
string |
Specifies the authentication method for OpenID.
For more information, see Authentication using OpenID. |
autocommit
|
boolean [0 | 1] |
Enables/disables autocommit.
Default: enabled |
clientname
|
string |
Defines the name of the client sent to the server. Default: |
clientversion
|
string |
Defines the version of the client sent to the server. Default: empty |
connectionPoolSize
|
numeric ≥0, <8192 |
Changes the maximum size of the connection pool (the number of connections). You can change this value only once in the driver instance. Default: 64 |
debug
|
boolean [0 | 1] |
Enables/disables the driver’s log function. When enabled, the driver writes a log file named
Default: disabled To avoid performance issues, do not enable logging in a production system. |
enablenumerictypeconversion
|
boolean [0 | 1] |
When enabled, the driver will convert column decimal data types of a result set into integer types such as int or longint.
Default: enabled |
encryption
|
boolean [0 | 1] |
Enables/disables automatic encryption.
Default: enabled |
feedbackinterval
|
integer ≥0 |
The interval in seconds between the feedback messages that the server sends to the client during a query. This feedback does the following:
Default: 1 (second) Setting a very high feedback interval value may cause a long lag time before a command is canceled. |
fetchsize
|
numeric ≥0 |
The amount of data in KiB that should be obtained by Exasol during a fetch. The fetch size can also be set by using the function Default: 2000 (KiB) If this value is set very high, the JVM can run out of memory. |
fingerprint
|
string |
If TLS validation fails and you trust the server, you can use this parameter to include the server fingerprint in the connection string. For example:
To bypass TLS certificate checking, use the
IMPORTANT: A connection string must only contain a single fingerprint, specified either after the host or port or in a |
hosttimeout
|
numeric ≥0 |
Specifies the connection timeout in milliseconds for each TCP connection attempt. If multiple hosts are specified in the connection string, each host will wait for the specified time for a successful connection. Default: 2000 (ms) |
ignoreparams
|
string |
Optional comma-separated list of string parameters to be ignored by the driver’s spell checker. For example: |
kerberoshostname
|
string |
Host name of the Kerberos service. Default: the host name in the connection string |
kerberosservicename
|
string |
Principal name of the Kerberos service. Default: |
keystore
|
string |
When using a self signed certificate in JDBC, the certificate must be added to either the system default keystore or to a keystore that you have created.
Default: system default keystore |
keystorepassword
|
string |
A password for the keystore specified in This parameter is required if |
keystoretype
|
string |
The keystore type is optional. If the parameter is not set, the system keystore type is used. For information about valid keystore types, refer to the documentation for the JRE/JDK version used. Default: system keystore type |
legacyencryption
|
boolean [0 | 1] |
Enables use of the old ChaCha encryption for the client-server communication and disables the new TLS encryption.
Default: disabled (TLS encryption enabled) |
logdir
|
string |
The directory that JDBC debug log files are written to in debug mode. If this parameter is not defined, the logs are written to the application’s current directory. Because of this, we recommend that you always specify a log directory in debug mode. Example: Default: current directory |
logintimeout
|
numeric ≥0 |
The maximum time in milliseconds that the driver will wait to establish a connection. This timeout is required to limit the overall login time, especially in the case of a large cluster with several reserve nodes. Default: no timeout (driver will wait indefinitely for the connection to be established) |
logintype
|
[1 | 2 | SSPI | GSSAPI] |
Specifies the interface used for authentication. SSPI is the Windows implementation of GSSAPI and will be used by default on Windows systems. On non-Windows systems, GSSAPI is used by default. You can override this by setting this parameter explicitly.
Default on Windows systems: SSPI Default on non-Windows systems: GSSAPI |
querytimeout
|
numeric ≥0 |
Defines the time in seconds for a statement to run before it is automatically aborted. Default: 0 (infinite) |
schema
|
string |
Name of the schema that should be opened after login. If the schema cannot be opened, the login fails with a Default: empty (no schema) |
snapshottransactions
|
boolean [0 | 1] |
Enables/disables snapshot transactions for the session.
Default: session default |
socketfactory
|
string |
The socket factory to use when connecting to the server. Default: none |
superconnection
|
boolean [Y | N] |
When enabled, the user can execute queries even if the limit for active sessions (executing a query) has been reached.
Only the SYS user can set this parameter.
Default: database default |
validateservercertificate
|
boolean [0 | 1] |
Enables or disables the TLS server certificate validation.
Default: enabled |
worker |
boolean [0 | 1] |
Enables/disables sub-connections for parallel read and insert. For more details and examples, see this Exasol Knowledge Base article.
Default: disabled |
workertoken
|
numeric ≥0 |
This token is required when establishing parallel sub-connections. For more details and examples, see this Exasol Knowledge Base article. Default: 0 |
Best practices
-
Allocate enough memory for JVM
-
When operating on big tables, you can get problems if the available memory for the JVM is not big enough. Make sure that you allocate enough memory to handle the table data in your database.
-
Optimize the fetch size for reading big data volumes
-
The parameter
fetchsize
determines the data volume in KiB that should be fetched from the database in each round. If this value is too low, the data transfer may take longer to complete. If this value is too high, the JVM may run out of memory.The recommended fetch size is 1000 to 2000 KiB.
-
Use prepared statements
-
Instead of using single insert statements like
INSERT INTO t VALUES 1, 2, ...
, use the more efficient interface of prepared statements and their parameters. Prepared statements achieve optimal performance when using parameter sets between 500 KiB and 20 MiB. -
Use native data types
-
Insert data using native data types. For example, for the number
1234
useSQL_C_SLONG
(integer) instead ofSQL_CHAR
. -
Free up unused resources
-
Free up unused resources immediately. For example, for prepared statements, use
close()
. -
Limit the number of servers in the connection
-
Do not specify an unnecessarily wide range of IP addresses. Since the addresses in the specified range are randomly tried until a successful connection is made, the time required to complete the
connect
operation can be much longer with a large number of addresses.