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

Typically, data about data is called metadata.DatabaseMetaDataThe 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 methodsDatabaseMetaDataClass.

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()); } }

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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