edu.udo.cs.miningmart.db
Class DbCoreMysql

java.lang.Object
  edu.udo.cs.miningmart.db.DbCore
      edu.udo.cs.miningmart.db.DbCoreMysql

public class DbCoreMysql
extends DbCore

This class provides an access to a MySQL DBMS. It has only been tested with MySQL version 5.0.3. See www.mysql.com To compile this class, the MySQL JDBC driver package must be added to the classpath.

Version:

$Id: DbCoreMysql.java,v 1.4 2006/10/02 08:58:56 euler Exp $

Author:

Timm Euler

Field Summary

static java.lang.String	MYSQL_TYPE_CHAR The public constant indicating the Mysql Datatype CHAR
static java.lang.String	MYSQL_TYPE_DATE The public constant indicating the Mysql Datatype DATE
static java.lang.String	MYSQL_TYPE_INTEGER The public constant indicating the Mysql Datatype INTEGER
static java.lang.String	MYSQL_TYPE_NUMBER The public constant indicating the Mysql Datatype DOUBLE
static java.lang.String	MYSQL_TYPE_STRING The public constant indicating the Mysql Datatype VARCHAR
static java.lang.String	MYSQL_TYPE_TEXT The public constant indicating the Mysql Datatype TEXT
static java.lang.String	MYSQL_TYPE_TIME The public constant indicating the Mysql Datatype TIME
static java.lang.String	MYSQL_TYPE_TIMESTAMP The public constant indicating the Mysql Datatype TIMESTAMP

Fields inherited from class edu.udo.cs.miningmart.db.DbCore

DBMS_MYSQL, DBMS_ORACLE, DBMS_POSTGRES, mySchemaName

Constructor Summary

DbCoreMysql(java.lang.String url, java.lang.String dbName, java.lang.String user, java.lang.String passwd, M4InterfaceContext cal, boolean isM4Schema)
The constructor of this class calls the constructor of the superclass DbCore.

Method Summary

void	createForeignKeyConstraint(java.lang.String fkTableName, java.util.Collection fkAttributeNames, java.lang.String pkTableName, java.util.Collection pkAttributeNames, java.lang.String dbConstraintName) This method creates a foreign key constraint in the database.
java.lang.String	createPrimaryKeyConstraint(java.lang.String tableName, java.util.Collection pkAttributeNames, java.lang.String dbConstraintName) Creates a primary key constraint in the database.
boolean	dropRelation(java.lang.String tableName) Try to drop the table or view with the given name, if it exists.
java.lang.String	getAliasExpressionForInnerSelects(java.lang.String aliasName) Abstract method to be implemented by the subclasses.
java.lang.String	getAttributeForColumnNames() Abstract method to be implemented by the subclasses.
java.lang.String	getAttributeForColumnTypes() Abstract method to be implemented by the subclasses.
java.lang.String	getDatatypeName(java.lang.String m4RelDatatypeName, int size) This method returns the DBMS-dependent name of the datatype which the current DBMS uses to realize the given M4-Relational Datatype.
short	getDbms() Indicates the DBMS used.
java.lang.String	getFloorExpression() Abstract method to be implemented by the subclasses.
java.lang.String	getM4DatatypeName(java.lang.String dbmsDatatypeName) This method returns the M4-Relational Datatype that corresponds to the given DBMS-dependent name of a datatype.
protected long	getNextM4SequenceValue(java.sql.Statement stmt)
long	getNumberOfMonthsBetween(java.lang.String dbObjectName, java.lang.String firstValue, java.lang.String secondValue) Abstract method to be implemented by the subclasses.
java.lang.String	getPowerExpression(java.lang.String base, java.lang.String exponent) Abstract method to be implemented by the subclasses.
java.util.Collection	getPrimaryKeyColumnNames(java.lang.String dbObjectName) Returns a Collection with the names of the DB columns that belong to the given table or view and form its primary key, if such a key is declared by SQL constraints in the DB.
java.lang.String	getRoundToDecimalPlacesExpression() Abstract method to be implemented by the subclasses.
java.lang.String	getSelectStringAllColumnsForDbObject(java.lang.String dbObjectName) Abstract method to be implemented by the subclasses.
java.lang.String	getSelectStringAllTables() Abstract method to be implemented by the subclasses.
java.lang.String	getSelectStringAllViews() Abstract method to be implemented by the subclasses.
java.lang.String	getSelectStringColumnDataTypes(java.lang.String dbObjectName, java.lang.String owner, java.lang.String columnName) This method returns the DBMS-dependent SQL command that returns the name of the datatype of the given column in the given table or view (which is owned by the given owner).
java.lang.String	getSelectStringDistribValuesTimeColumn(java.lang.String colSql, java.lang.String tableName, java.lang.String distribBase) Returns the SQL string that selects distribution values from the given column (given by its name and the name of its table or view).
java.lang.String	getTableOrViewType(java.lang.String dbObjectName) Returns one of the TYPE_... constants in the class edu.udo.cs.miningmart.m4.Columnset, or null if the given String is neither a table or view.
java.util.Map	getTablesReferencedBy(java.lang.String dbObjectName) Returns a Map that maps every column of the given table to the name of the table that it references as a foreign key, or to null if the column does not act as a foreign key.
java.util.Map	getTablesReferringTo(java.lang.String dbObjectName) Returns a Map that maps every column of the given table to a list with names of the tables that refer to it as a foreign key, or to null if no other column refers to it.
java.lang.String	getTestQuery()
java.lang.String	getUniqueRowIdentifier() WARNING: the unique row identifier works only for tables with a single primary key column of type integer!
protected void	registerJDBC_Driver() Implements the superclass method so that the correct JDBC driver for MySQL is used.
protected void	switchAutocommitOff(java.sql.Connection con) Since the transaction mechanism may be different for different DBMS, use this method to implement the Autocommit handling.
boolean	tableExists(java.lang.String tableName) Returns TRUE if a table (not a view) with the given name exists in the database.

Methods inherited from class edu.udo.cs.miningmart.db.DbCore

commitBatch, commitTransactions, createSQLFunction, createSqlIndex, createSQLView, executeDBProcedure, executeSingleValueSqlRead, executeSingleValueSqlReadL, executeSingleValueSqlReadL, executeSqlRead, executeSqlWrite, executeSqlWrite, finalize, findDBMS, getCasePrintObject, getColumnTestQuery, getComparisonOp, getDbReadStatement, getDbWriteStatement, hasOnlyForeignKeyColumns, isColumnUsedAsPrimaryKey, rollback, stringCollectionToCommaSeparated

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MYSQL_TYPE_NUMBER

public static final java.lang.String MYSQL_TYPE_NUMBER

The public constant indicating the Mysql Datatype DOUBLE

See Also:

Constant Field Values

MYSQL_TYPE_INTEGER

public static final java.lang.String MYSQL_TYPE_INTEGER

The public constant indicating the Mysql Datatype INTEGER

See Also:

Constant Field Values

MYSQL_TYPE_STRING

public static final java.lang.String MYSQL_TYPE_STRING

The public constant indicating the Mysql Datatype VARCHAR

See Also:

Constant Field Values

MYSQL_TYPE_CHAR

public static final java.lang.String MYSQL_TYPE_CHAR

The public constant indicating the Mysql Datatype CHAR

See Also:

Constant Field Values

MYSQL_TYPE_DATE

public static final java.lang.String MYSQL_TYPE_DATE

The public constant indicating the Mysql Datatype DATE

See Also:

Constant Field Values

MYSQL_TYPE_TIME

public static final java.lang.String MYSQL_TYPE_TIME

The public constant indicating the Mysql Datatype TIME

See Also:

Constant Field Values

MYSQL_TYPE_TIMESTAMP

public static final java.lang.String MYSQL_TYPE_TIMESTAMP

The public constant indicating the Mysql Datatype TIMESTAMP

See Also:

Constant Field Values

MYSQL_TYPE_TEXT

public static final java.lang.String MYSQL_TYPE_TEXT

The public constant indicating the Mysql Datatype TEXT

See Also:

Constant Field Values

Constructor Detail

DbCoreMysql

public DbCoreMysql(java.lang.String url,
                   java.lang.String dbName,
                   java.lang.String user,
                   java.lang.String passwd,
                   M4InterfaceContext cal,
                   boolean isM4Schema)
            throws java.sql.SQLException

The constructor of this class calls the constructor of the superclass DbCore. Autocommit is set to false, so transaction management must be done individually by the database functions.

Parameters:

url - Prefix of the database url

dbName - name of the database

user - name of the database user

passwd - password for the database user

cal - the CompilerAccessLogic of the current thread. It is just needed in order to reach the appropriate Print-object for writing debug messages

isM4Schema - is true iff the connection refers to the M4 schema. Useful to decide whether triggers need to be switched off etc.

Throws:

java.sql.SQLException

See Also:

edu.udo.cs.miningmart.m4.core.utils.DbCore#DbCore(String, String, String, String, CompilerAccessLogic, boolean)

Method Detail

registerJDBC_Driver

protected void registerJDBC_Driver()
                            throws java.sql.SQLException

Implements the superclass method so that the correct JDBC driver for MySQL is used.

Specified by:

registerJDBC_Driver in class DbCore

Throws:

java.sql.SQLException

getDbms

public short getDbms()

Indicates the DBMS used.

Specified by:

getDbms in class DbCore

Returns:

The public static constant DB.MYSQL

switchAutocommitOff

protected void switchAutocommitOff(java.sql.Connection con)
                            throws java.sql.SQLException

Description copied from class: DbCore

Since the transaction mechanism may be different for different DBMS, use this method to implement the Autocommit handling.

Specified by:

switchAutocommitOff in class DbCore

Throws:

java.sql.SQLException

See Also:

DbCore#switchAutocommitOff()

getNextM4SequenceValue

protected long getNextM4SequenceValue(java.sql.Statement stmt)
                               throws M4Exception

Specified by:

getNextM4SequenceValue in class DbCore

Parameters:

stmt - the Statement to be used to execute the query

Returns:

the value returned by the sequence (installed in the M4 schema).

Throws:

M4Exception - if for some reason the sequence does not return a value

See Also:

DbCore.getNextM4SequenceValue(Statement)

getSelectStringAllTables

public java.lang.String getSelectStringAllTables()

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns an SQL String that selects the names of all tables from the current schema. This is DBMS-dependent.

Specified by:

getSelectStringAllTables in class DbCore

Returns:

An SQL String

See Also:

DbCore

getSelectStringAllViews

public java.lang.String getSelectStringAllViews()

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns an SQL String that selects the names of all views from the current schema. This is DBMS-dependent.

Specified by:

getSelectStringAllViews in class DbCore

Returns:

An SQL String

See Also:

DbCore

getSelectStringDistribValuesTimeColumn

public java.lang.String getSelectStringDistribValuesTimeColumn(java.lang.String colSql,
                                                               java.lang.String tableName,
                                                               java.lang.String distribBase)

Description copied from class: DbCore

Returns the SQL string that selects distribution values from the given column (given by its name and the name of its table or view). The given distribution base determines the granularity of aggregation. In this way daywise or monthwise values can be selected, for example.

Specified by:

getSelectStringDistribValuesTimeColumn in class DbCore

Parameters:

colSql - string that determines the column in the given table or view

tableName - name of a table or view

distribBase - granularity of values to be returned by the query

Returns:

a query

See Also:

DbCore

getSelectStringAllColumnsForDbObject

public java.lang.String getSelectStringAllColumnsForDbObject(java.lang.String dbObjectName)

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns the SQL String that selects all column names and types for the given Table or View name from the business data schema. This is DBMS-dependent.

Specified by:

getSelectStringAllColumnsForDbObject in class DbCore

Parameters:

dbObjectName - Name of a table OR view in the business data schema

Returns:

An SQL String

See Also:

DbCore

getNumberOfMonthsBetween

public long getNumberOfMonthsBetween(java.lang.String dbObjectName,
                                     java.lang.String firstValue,
                                     java.lang.String secondValue)
                              throws M4Exception

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns the difference in months between two date values, looked up in the given DB object (table or view).

Specified by:

getNumberOfMonthsBetween in class DbCore

Returns:

Throws:

M4Exception

tableExists

public boolean tableExists(java.lang.String tableName)
                    throws M4Exception

Description copied from class: DbCore

Returns TRUE if a table (not a view) with the given name exists in the database.

Specified by:

tableExists in class DbCore

Parameters:

tableName - the table name

Returns:

TRUE or FALSE

Throws:

M4Exception

getSelectStringColumnDataTypes

public java.lang.String getSelectStringColumnDataTypes(java.lang.String dbObjectName,
                                                       java.lang.String owner,
                                                       java.lang.String columnName)

Description copied from class: DbCore

This method returns the DBMS-dependent SQL command that returns the name of the datatype of the given column in the given table or view (which is owned by the given owner).

Specified by:

getSelectStringColumnDataTypes in class DbCore

Parameters:

dbObjectName - Name of a table or view in the business data schema

owner - Name of the owner of the table or view (can be null)

columnName - Name of the column whose datatype is returned

Returns:

the DBMS-dependent name of the datatype of the column with the given name

See Also:

DbCore

getPrimaryKeyColumnNames

public java.util.Collection getPrimaryKeyColumnNames(java.lang.String dbObjectName)
                                              throws java.sql.SQLException,
                                                     DbConnectionClosed

Description copied from class: DbCore

Returns a Collection with the names of the DB columns that belong to the given table or view and form its primary key, if such a key is declared by SQL constraints in the DB. Otherwise null is returned.

Specified by:

getPrimaryKeyColumnNames in class DbCore

Parameters:

dbObjectName - the name of the given table or view

Returns:

a Collection of Strings

Throws:

java.sql.SQLException

DbConnectionClosed

See Also:

DbCore

getTablesReferencedBy

public java.util.Map getTablesReferencedBy(java.lang.String dbObjectName)
                                    throws java.sql.SQLException,
                                           DbConnectionClosed

Description copied from class: DbCore

Returns a Map that maps every column of the given table to the name of the table that it references as a foreign key, or to null if the column does not act as a foreign key. The Map uses only Strings.

Specified by:

getTablesReferencedBy in class DbCore

Parameters:

dbObjectName - the given table name

Returns:

a Map whose keys and values are Strings

Throws:

java.sql.SQLException

DbConnectionClosed

See Also:

DbCore

getTablesReferringTo

public java.util.Map getTablesReferringTo(java.lang.String dbObjectName)
                                   throws java.sql.SQLException,
                                          DbConnectionClosed

Description copied from class: DbCore

Returns a Map that maps every column of the given table to a list with names of the tables that refer to it as a foreign key, or to null if no other column refers to it. The Map uses only Strings.

Specified by:

getTablesReferringTo in class DbCore

Parameters:

dbObjectName - the given table name

Returns:

a Map whose keys and values are Strings

Throws:

java.sql.SQLException

DbConnectionClosed

See Also:

DbCore

getTableOrViewType

public java.lang.String getTableOrViewType(java.lang.String dbObjectName)
                                    throws java.sql.SQLException,
                                           DbConnectionClosed

Returns one of the TYPE_... constants in the class edu.udo.cs.miningmart.m4.Columnset, or null if the given String is neither a table or view.

Specified by:

getTableOrViewType in class DbCore

Parameters:

dbObjectName - name of a table or view

Returns:

a String with the type information

Throws:

java.sql.SQLException

DbConnectionClosed

getAttributeForColumnNames

public java.lang.String getAttributeForColumnNames()

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns the name of the column that contains the column names. This is DBMS-dependent.

Specified by:

getAttributeForColumnNames in class DbCore

Returns:

the name of the column that contains the column names

See Also:

DbCore

getAttributeForColumnTypes

public java.lang.String getAttributeForColumnTypes()

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns the name of the column that contains the column types. This is DBMS-dependent.

Specified by:

getAttributeForColumnTypes in class DbCore

Returns:

the name of the column that contains the column types

See Also:

DbCore

getUniqueRowIdentifier

public java.lang.String getUniqueRowIdentifier()

WARNING: the unique row identifier works only for tables with a single primary key column of type integer!

Specified by:

getUniqueRowIdentifier in class DbCore

Returns:

the unique row identifier name

See Also:

DbCore

getPowerExpression

public java.lang.String getPowerExpression(java.lang.String base,
                                           java.lang.String exponent)

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns a String that can be used to in a SQL statement and that computes the power of the base to the exponent. This string is DBMS-dependent.

Specified by:

getPowerExpression in class DbCore

Returns:

a string with the power expression

See Also:

DbCore

getFloorExpression

public java.lang.String getFloorExpression()

Abstract method to be implemented by the subclasses. Returns a String that can be used to in a SQL statement and that computes the floor of some argument, ie the largest integer that is smaller than or equal to the argument. This string is DBMS-dependent.

Specified by:

getFloorExpression in class DbCore

Returns:

a string with the floor expression

getRoundToDecimalPlacesExpression

public java.lang.String getRoundToDecimalPlacesExpression()

Abstract method to be implemented by the subclasses. Returns a String that can be used to in a SQL statement and that rounds some numeric argument to n decimal places. This string is DBMS-dependent.

Specified by:

getRoundToDecimalPlacesExpression in class DbCore

Returns:

a string with the rounding expression

getAliasExpressionForInnerSelects

public java.lang.String getAliasExpressionForInnerSelects(java.lang.String aliasName)

Description copied from class: DbCore

Abstract method to be implemented by the subclasses. Returns a String that can be used to in a SQL statement that involves a SELECT inside a FROM, to alias this inner view definition.

Specified by:

getAliasExpressionForInnerSelects in class DbCore

Returns:

a string with the alias expression

See Also:

DbCore

getDatatypeName

public java.lang.String getDatatypeName(java.lang.String m4RelDatatypeName,
                                        int size)

Description copied from class: DbCore

This method returns the DBMS-dependent name of the datatype which the current DBMS uses to realize the given M4-Relational Datatype.

Specified by:

getDatatypeName in class DbCore

Parameters:

m4RelDatatypeName - name of the M4 Relational Datatype

size - A size to be returned with the datatype, if the DBMS allows that. For example, if the M4 Relational Datatype is NUMBER and length is 10, then the return value will be the String "NUMBER(10)" if the DBMS is Oracle. If this length is not positive, the datatype will be returned without a size, in the example: "NUMBER". The DBMS may not allow lengths at all, in which case also the datatype without a size is returned.

Returns:

A DBMS-dependent string that contains a datatype name.

See Also:

DbCore

getM4DatatypeName

public java.lang.String getM4DatatypeName(java.lang.String dbmsDatatypeName)

Description copied from class: DbCore

This method returns the M4-Relational Datatype that corresponds to the given DBMS-dependent name of a datatype.

Specified by:

getM4DatatypeName in class DbCore

Parameters:

dbmsDatatypeName - the name of the datatype in the underlying DBMS

Returns:

the corresponding M4 Relational Datatype

See Also:

DbCore

dropRelation

public boolean dropRelation(java.lang.String tableName)
                     throws M4Exception

Try to drop the table or view with the given name, if it exists. Returns TRUE iff the table had existed, FALSE otherwise.

Specified by:

dropRelation in class DbCore

Parameters:

tableName - the name of the table to be dropped

Returns:

TRUE iff the table had existed before it was removed, FALSE if nothing was done.

Throws:

M4Exception

getTestQuery

public java.lang.String getTestQuery()

Specified by:

getTestQuery in class DbCore

Returns:

a String that can be used as a query to test the DB connection.

createPrimaryKeyConstraint

public java.lang.String createPrimaryKeyConstraint(java.lang.String tableName,
                                                   java.util.Collection pkAttributeNames,
                                                   java.lang.String dbConstraintName)
                                            throws java.sql.SQLException,
                                                   DbConnectionClosed

Creates a primary key constraint in the database.

Specified by:

createPrimaryKeyConstraint in class DbCore

Parameters:

tableName - The table for which to add the constraint

pkAttributeNames - a Collection of Strings, each with the name of a primary key attribute (relational level)

dbConstraintName - a unique name for the database constraint, or null to use a generic name

Returns:

the name of the database constraint

Throws:

java.sql.SQLException

DbConnectionClosed

createForeignKeyConstraint

public void createForeignKeyConstraint(java.lang.String fkTableName,
                                       java.util.Collection fkAttributeNames,
                                       java.lang.String pkTableName,
                                       java.util.Collection pkAttributeNames,
                                       java.lang.String dbConstraintName)
                                throws java.sql.SQLException,
                                       DbConnectionClosed

This method creates a foreign key constraint in the database.

Specified by:

createForeignKeyConstraint in class DbCore

Parameters:

fkTableName - The name of the table to create the constraint for.

fkAttributeNames - Collection of attribute names (relational level) part of the fkTableName table that point to the primary key attributes of pkTableName.

pkTableName - The name of the referenced table.

pkAttributeNames - Collection of attribute names that constitute the primary key of the referenced table

dbConstraintName - unique name of the database constraint, must not be null

Throws:

java.sql.SQLException

DbConnectionClosed