What is DatabaseMetaData in JDBC? What's the point?

Typically, data about data is called metadata. DatabaseMetaData The interface provides some methods to get information about the database you are connected to, such as database name, database driver version, maximum column length, etc...

Here are some methodsDatabaseMetaData Class.

DescriptionRetrieve the name of the current JDBC driverRetrieve the version of the current JDBC driverRetrieve the user name. Retrieve the name of the current database. Retrieve the version of the current database. Retrieves a list of numeric functions available for this database. Retrieves a list of numeric functions available for this database. Retrieve the list of system functions available for this database. Retrieves a list of time and date functions available for this database. Retrieve the URL of the current database. Verify the weather support stored procedure for the current database. Verify whether the current database supports transactions.

Method
##getDriverName()
getDriverVersion()	td>
getUserName()
getDatabaseProductName()
getDatabaseProductVersion()
getNumericFunctions()
getStringFunctions()	td>
getSystemFunctions()
getTimeDateFunctions()
getURL()
supportsSavepoints()Verify whether the current database supports savepoints
supportsStoredProcedures ()
supportsTransactions()

Example

The following example demonstrates the use of the DatabaseMetaData class.

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
public class DatabaseMetadataExample {
   public static void main(String args[])throws Exception {
      //Getting the connection
      String mysqlUrl = "jdbc:mysql://localhost/sampleDB";
      Connection con = DriverManager.getConnection(mysqlUrl, "root", "password");
      System.out.println("Connection established......");

      //Creating the DatabaseMetaData object
      DatabaseMetaData dbMetadata = con.getMetaData();
      //invoke the supportsBatchUpdates() method.
      boolean bool = dbMetadata.supportsBatchUpdates();

      if(bool) {
         System.out.println("Underlying database supports batch updates");
      } else {
         System.out.println("Underlying database doesnt supports batch updates");
      }

      //Retrieving the driver name
      System.out.println(dbMetadata.getDriverName());
      //Retrieving the driver version
      System.out.println(dbMetadata.getDriverVersion());
      //Retrieving the user name
      System.out.println(dbMetadata.getUserName());
      //Retrieving the URL
      System.out.println(dbMetadata.getURL());
      //Retrieving the list of numeric functions
      System.out.println("Numeric functions: "+dbMetadata.getNumericFunctions());
      System.out.println("");
      //Retrieving the list of String functions
      System.out.println("String functions: "+dbMetadata.getStringFunctions());
      System.out.println("");
      //Retrieving the list of system functions
      System.out.println("System functions: "+dbMetadata.getSystemFunctions());
      System.out.println("");
      //Retrieving the list of time and date functions
      System.out.println("Time and Date funtions: "+dbMetadata.getTimeDateFunctions());
   }
}

Output

Connection established......
Underlying database supports batch updates
MySQL-AB JDBC Driver
mysql-connector-java-5.1.12 ( Revision: ${bzr.revision-id} )
root@localhost
jdbc:mysql://localhost/sampleDB
Numeric functions:
ABS,ACOS,ASIN,ATAN,ATAN2,BIT_COUNT,CEILING,COS,COT,DEGREES,EXP,FLOOR,LOG,LOG10,MAX
,MIN,MOD,PI,POW,POWER,RADIANS,RAND,ROUND,SIN,SQRT,TAN,TRUNCATE
String functions:
ASCII,BIN,BIT_LENGTH,CHAR,CHARACTER_LENGTH,CHAR_LENGTH,CONCAT,CONCAT_WS,CONV,ELT,E
XPORT_SET,FIELD,FIND_IN_SET,HEX,INSERT,INSTR,LCASE,LEFT,LENGTH,LOAD_FILE,LOCATE,LO
CATE,LOWER,LPAD,LTRIM,MAKE_SET,MATCH,MID,OCT,OCTET_LENGTH,ORD,POSITION,QUOTE,REPEA
T,REPLACE,REVERSE,RIGHT,RPAD,RTRIM,SOUNDEX,SPACE,STRCMP,SUBSTRING,SUBSTRING,SUBSTR
ING,SUBSTRING,SUBSTRING_INDEX,TRIM,UCASE,UPPER
System functions:
DATABASE,USER,SYSTEM_USER,SESSION_USER,PASSWORD,ENCRYPT,LAST_INSERT_ID,VERSION
Time and Date funtions:
DAYOFWEEK,WEEKDAY,DAYOFMONTH,DAYOFYEAR,MONTH,DAYNAME,MONTHNAME,QUARTER,WEEK,YEAR,H
OUR,MINUTE,SECOND,PERIOD_ADD,PERIOD_DIFF,TO_DAYS,FROM_DAYS,DATE_FORMAT,TIME_FORMAT
,CURDATE,CURRENT_DATE,CURTIME,CURRENT_TIME,NOW,SYSDATE,CURRENT_TIMESTAMP,UNIX_TIME
STAMP,FROM_UNIXTIME,SEC_TO_TIME,TIME_TO_SEC

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