How to Execute SQL Script File in Java?

I want to execute an SQL script file in Java without reading the entire file content into a big quer开发者_高级运维y and executing it.

Is there any other standard way?

There is great way of executing SQL scripts from Java without reading them yourself as long as you don't mind having a dependency on Ant. In my opinion such a dependency is very well justified in your case. Here is sample code, where SQLExec class lives in ant.jar:

private void executeSql(String sqlFilePath) {
    final class SqlExecuter extends SQLExec {
        public SqlExecuter() {
            Project project = new Project();
            project.init();
            setProject(project);
            setTaskType("sql");
            setTaskName("sql");
        }
    }

    SqlExecuter executer = new SqlExecuter();
    executer.setSrc(new File(sqlFilePath));
    executer.setDriver(args.getDriver());
    executer.setPassword(args.getPwd());
    executer.setUserid(args.getUser());
    executer.setUrl(args.getUrl());
    executer.execute();
}

There is no portable way of doing that. You can execute a native client as an external program to do that though:

import java.io.*;
public class CmdExec {

  public static void main(String argv[]) {
    try {
      String line;
      Process p = Runtime.getRuntime().exec
        ("psql -U username -d dbname -h serverhost -f scripfile.sql");
      BufferedReader input =
        new BufferedReader
          (new InputStreamReader(p.getInputStream()));
      while ((line = input.readLine()) != null) {
        System.out.println(line);
      }
      input.close();
    }
    catch (Exception err) {
      err.printStackTrace();
    }
  }
}

• Code sample was extracted from here and modified to answer question assuming that the user wants to execute a PostgreSQL script file.

Flyway library is really good for this:

    Flyway flyway = new Flyway();
    flyway.setDataSource(dbConfig.getUrl(), dbConfig.getUsername(), dbConfig.getPassword());
    flyway.setLocations("classpath:db/scripts");
    flyway.clean();
    flyway.migrate();

This scans the locations for scripts and runs them in order. Scripts can be versioned with V01__name.sql so if just the migrate is called then only those not already run will be run. Uses a table called 'schema_version' to keep track of things. But can do other things too, see the docs: flyway.

The clean call isn't required, but useful to start from a clean DB. Also, be aware of the location (default is "classpath:db/migration"), there is no space after the ':', that one caught me out.

No, you must read the file, split it into separate queries and then execute them individually (or using the batch API of JDBC).

One of the reasons is that every database defines their own way to separate SQL statements (some use ;, others /, some allow both or even to define your own separator).

You cannot do using JDBC as it does not support . Work around would be including iBatis iBATIS is a persistence framework and call the Scriptrunner constructor as shown in iBatis documentation .

Its not good to include a heavy weight persistence framework like ibatis in order to run a simple sql scripts any ways which you can do using command line

$ mysql -u root -p db_name < test.sql

Since JDBC doesn't support this option the best way to solve this question is executing command lines via the Java Program. Bellow is an example to postgresql:

private void executeSqlFile() {
     try {
         Runtime rt = Runtime.getRuntime();
         String executeSqlCommand = "psql -U (user) -h (domain) -f (script_name) (dbName)";
         Process pr = rt.exec();
         int exitVal = pr.waitFor();
         System.out.println("Exited with error code " + exitVal);
      } catch (Exception e) {
        System.out.println(e.toString());
      }
}

The Apache iBatis solution worked like a charm.

The script example I used was exactly the script I was running from MySql workbench.

There is an article with examples here: https://www.tutorialspoint.com/how-to-run-sql-script-using-jdbc#:~:text=You%20can%20execute%20.,to%20pass%20a%20connection%20object.&text=Register%20the%20MySQL%20JDBC%20Driver,method%20of%20the%20DriverManager%20class.

This is what I did:

pom.xml dependency

<!-- IBATIS SQL Script runner from Apache (https://mvnrepository.com/artifact/org.apache.ibatis/ibatis-core) -->
<dependency>
    <groupId>org.apache.ibatis</groupId>
    <artifactId>ibatis-core</artifactId>
    <version>3.0</version>
</dependency>

Code to execute script:

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.Reader;
import java.sql.Connection;   
import org.apache.ibatis.jdbc.ScriptRunner;   
import lombok.extern.slf4j.Slf4j;

@Slf4j
public class SqlScriptExecutor {

    public static void executeSqlScript(File file, Connection conn) throws Exception {
        Reader reader = new BufferedReader(new FileReader(file));
        log.info("Running script from file: " + file.getCanonicalPath());
        ScriptRunner sr = new ScriptRunner(conn);
        sr.setAutoCommit(true);
        sr.setStopOnError(true);
        sr.runScript(reader);
        log.info("Done.");
    }
    
}

For my simple project the user should be able to select SQL-files which get executed. As I was not happy with the other answers and I am using Flyway anyway I took a closer look at the Flyway code. DefaultSqlScriptExecutor is doing the actual execution, so I tried to figure out how to create an instance of DefaultSqlScriptExecutor.

Basically the following snippet loads a String splits it into the single statements and executes one by one. Flyway also provides other LoadableResources than StringResource e.g. FileSystemResource. But I have not taken a closer look at them.

As DefaultSqlScriptExecutor and the other classes are not officially documented by Flyway use the code-snippet with care.

public static void execSqlQueries(String sqlQueries, Configuration flyWayConf) throws SQLException {
  // create dependencies FlyWay needs to execute the SQL queries
  JdbcConnectionFactory jdbcConnectionFactory = new JdbcConnectionFactory(flyWayConf.getDataSource(),
      flyWayConf.getConnectRetries(),
      null);
  DatabaseType databaseType = jdbcConnectionFactory.getDatabaseType();
  ParsingContext parsingContext = new ParsingContext();
  SqlScriptFactory sqlScriptFactory = databaseType.createSqlScriptFactory(flyWayConf, parsingContext);
  Connection conn = flyWayConf.getDataSource().getConnection();
  JdbcTemplate jdbcTemp = new JdbcTemplate(conn);
  ResourceProvider resProv = flyWayConf.getResourceProvider();
  DefaultSqlScriptExecutor scriptExec = new DefaultSqlScriptExecutor(jdbcTemp, null, false, false, false, null);
  
  // Prepare and execute the actual queries
  StringResource sqlRes = new StringResource(sqlQueries);
  SqlScript sqlScript = sqlScriptFactory.createSqlScript(sqlRes, true, resProv);
  scriptExec.execute(sqlScript);
}

The simplest external tool that I found that is also portable is jisql - https://www.xigole.com/software/jisql/jisql.jsp . You would run it as:

java -classpath lib/jisql.jar:\
          lib/jopt-simple-3.2.jar:\
          lib/javacsv.jar:\
           /home/scott/postgresql/postgresql-8.4-701.jdbc4.jar 
    com.xigole.util.sql.Jisql -user scott -password blah     \
    -driver postgresql                                       \
    -cstring jdbc:postgresql://localhost:5432/scott -c \;    \
    -query "select * from test;"

JDBC does not support this option (although a specific DB driver may offer this). Anyway, there should not be a problem with loading all file contents into memory.

Try this code:

String strProc =
         "DECLARE \n" +
         "   sys_date DATE;"+
         "" +
         "BEGIN\n" +
         "" +
         "   SELECT SYSDATE INTO sys_date FROM dual;\n" +
         "" +
         "END;\n";

try{
    DriverManager.registerDriver ( new oracle.jdbc.driver.OracleDriver () );
    Connection connection = DriverManager.getConnection ("jdbc:oracle:thin:@your_db_IP:1521:your_db_SID","user","password");  
    PreparedStatement psProcToexecute = connection.prepareStatement(strProc);
    psProcToexecute.execute();
}catch (Exception e) {
    System.out.println(e.toString());  
}

If you use Spring you can use DataSourceInitializer:

@Bean
public DataSourceInitializer dataSourceInitializer(@Qualifier("dataSource") final DataSource dataSource) {
    ResourceDatabasePopulator resourceDatabasePopulator = new ResourceDatabasePopulator();
    resourceDatabasePopulator.addScript(new ClassPathResource("/data.sql"));
    DataSourceInitializer dataSourceInitializer = new DataSourceInitializer();
    dataSourceInitializer.setDataSource(dataSource);
    dataSourceInitializer.setDatabasePopulator(resourceDatabasePopulator);
    return dataSourceInitializer;
}

Used to set up a database during initialization and clean up a database during destruction.

https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/jdbc/datasource/init/DataSourceInitializer.html