edu.udo.cs.miningmart.db
Class DbCore

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

Direct Known Subclasses:

DbCoreMysql, DbCoreOracle, DbCorePostgres

public abstract class DbCore
extends java.lang.Object

Abstract superclass class to encapsulate most of the directly database related information. Subclasses realise the access to different DBMS. The only class referencing subclasses of DbCore is DB. However, the class is public because it provides static methods to deal with different DBMS systems.

Version:

$Id: DbCore.java,v 1.17 2006/10/02 08:58:56 euler Exp $

Author:

Martin Scholz

Field Summary

static java.lang.String	DBMS_MYSQL Public constant to refer to the Database Management System (DBMS) MySQL.
static java.lang.String	DBMS_ORACLE Public constant to refer to the Database Management System (DBMS) Oracle.
static java.lang.String	DBMS_POSTGRES Public constant to refer to the Database Management System (DBMS) PostgreSQL.
protected java.lang.String	mySchemaName

Constructor Summary

DbCore(java.lang.String url, java.lang.String dbName, java.lang.String user, java.lang.String passwd, M4InterfaceContext cal, boolean refersToM4Schema)
The constructor of this class establishes a new database connection.

Method Summary

protected static void	commitBatch(java.sql.Statement stmt) commits and clears a batch
void	commitTransactions() Commit the last transactions in the M4 database.
abstract 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.
abstract java.lang.String	createPrimaryKeyConstraint(java.lang.String tableName, java.util.Collection pkAttributeNames, java.lang.String dbConstraintName) Creates a primary key constraint in the database.
void	createSQLFunction(java.lang.String myFunction) Create a function in the database by using the given function definition.
java.lang.String	createSqlIndex(java.lang.String tableName, java.lang.String[] attributes) Creates a database index for the given table and set of attributes.
void	createSQLView(Columnset cs, boolean materialize) Create the generated sql definition for a new view within the database, or materialize the view as a table, if this is preferrable.
abstract boolean	dropRelation(java.lang.String tableName) Try to drop the table or view with the given name, if it exists.
void	executeDBProcedure(java.lang.String procedureName, java.lang.String[] parameters) Method to execute a stored procedure residing in the according schema.
java.lang.String	executeSingleValueSqlRead(java.lang.String query)
java.lang.Long	executeSingleValueSqlReadL(java.lang.String query)
protected java.lang.Long	executeSingleValueSqlReadL(java.lang.String query, java.sql.Statement stmt)
java.sql.ResultSet	executeSqlRead(java.lang.String query) Method to comfortably read from the database.
void	executeSqlWrite(java.lang.String query) Method to comfortably write to the database.
protected void	executeSqlWrite(java.lang.String query, java.sql.Statement stmt)
void	finalize() Closes the database connections.
static java.lang.String	findDBMS(java.lang.String url) Use this method to decide about the Database Management System (DBMS) which is to be used.
abstract java.lang.String	getAliasExpressionForInnerSelects(java.lang.String aliasName) Abstract method to be implemented by the subclasses.
abstract java.lang.String	getAttributeForColumnNames() Abstract method to be implemented by the subclasses.
abstract java.lang.String	getAttributeForColumnTypes() Abstract method to be implemented by the subclasses.
Print	getCasePrintObject()
java.lang.String	getColumnTestQuery(Column col) Returns a string that can be used as a query.
protected java.lang.String	getComparisonOp(boolean greater, boolean orEqual)
abstract 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.
abstract short	getDbms() Indicates the DBMS used.
protected java.sql.Statement	getDbReadStatement()
protected java.sql.Statement	getDbWriteStatement()
abstract java.lang.String	getFloorExpression() Abstract method to be implemented by the subclasses.
abstract 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 abstract long	getNextM4SequenceValue(java.sql.Statement stmt)
abstract long	getNumberOfMonthsBetween(java.lang.String dbObjectName, java.lang.String firstValue, java.lang.String secondValue) Abstract method to be implemented by the subclasses.
abstract java.lang.String	getPowerExpression(java.lang.String base, java.lang.String exponent) Abstract method to be implemented by the subclasses.
abstract 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.
abstract java.lang.String	getRoundToDecimalPlacesExpression() Abstract method to be implemented by the subclasses.
abstract java.lang.String	getSelectStringAllColumnsForDbObject(java.lang.String dbObjectName) Abstract method to be implemented by the subclasses.
abstract java.lang.String	getSelectStringAllTables() Abstract method to be implemented by the subclasses.
abstract java.lang.String	getSelectStringAllViews() Abstract method to be implemented by the subclasses.
abstract 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).
abstract 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).
abstract 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.
abstract 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.
abstract 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.
abstract java.lang.String	getTestQuery()
abstract java.lang.String	getUniqueRowIdentifier() Abstract method to be implemented by the subclasses.
boolean	hasOnlyForeignKeyColumns(java.lang.String dbObjectName) Returns TRUE iff the given table/view has ONLY columns that act as foreign keys to other tables.
boolean	isColumnUsedAsPrimaryKey(java.lang.String columnName, java.lang.String dbObjectName)
protected abstract void	registerJDBC_Driver() This method must be implemented by subclasses in order to use other JDBC drivers (for other DBMS, for example).
void	rollback() Roll back the last transactions (since the last commit) in the database.
static java.lang.String	stringCollectionToCommaSeparated(java.util.Collection col) Helper method, turns collections of strings into comma separated strings.
protected abstract void	switchAutocommitOff(java.sql.Connection con) Since the transaction mechanism may be different for different DBMS, use this method to implement the Autocommit handling.
abstract 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 java.lang.Object

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

Field Detail

DBMS_ORACLE

public static java.lang.String DBMS_ORACLE

Public constant to refer to the Database Management System (DBMS) Oracle.

DBMS_POSTGRES

public static java.lang.String DBMS_POSTGRES

Public constant to refer to the Database Management System (DBMS) PostgreSQL.

DBMS_MYSQL

public static java.lang.String DBMS_MYSQL

Public constant to refer to the Database Management System (DBMS) MySQL.

mySchemaName

protected java.lang.String mySchemaName

Constructor Detail

DbCore

public DbCore(java.lang.String url,
              java.lang.String dbName,
              java.lang.String user,
              java.lang.String passwd,
              M4InterfaceContext cal,
              boolean refersToM4Schema)
       throws java.sql.SQLException

The constructor of this class establishes a new database connection. 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

refersToM4Schema - 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

Method Detail

findDBMS

public static java.lang.String findDBMS(java.lang.String url)

Use this method to decide about the Database Management System (DBMS) which is to be used. This method is given the DB connection URL (consisting of driver and location) and returns one of the public constants of this class whose name starts with "DBMS_". Currently, this method uses the driver name to decide about the DBMS.

Parameters:

url - The DB connection URL

Returns:

One of the public String constants of this class.

getCasePrintObject

public Print getCasePrintObject()

finalize

public void finalize()
              throws java.sql.SQLException

Closes the database connections. If the database is no longer used this Finalization method closes the database connection. Currently, I guess a java exit is an acceptable disconnect as well. If not we have to register a addShutdownHook in Class Runtime

Overrides:

finalize in class java.lang.Object

Throws:

java.sql.SQLException

getDbms

public abstract short getDbms()

Indicates the DBMS used.

registerJDBC_Driver

protected abstract void registerJDBC_Driver()
                                     throws java.sql.SQLException

This method must be implemented by subclasses in order to use other JDBC drivers (for other DBMS, for example).

Throws:

java.sql.SQLException

getComparisonOp

protected java.lang.String getComparisonOp(boolean greater,
                                           boolean orEqual)

switchAutocommitOff

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

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

Throws:

java.sql.SQLException

commitTransactions

public void commitTransactions()
                        throws java.sql.SQLException

Commit the last transactions in the M4 database.

Throws:

java.sql.SQLException

rollback

public void rollback()
              throws java.sql.SQLException

Roll back the last transactions (since the last commit) in the database.

Throws:

java.sql.SQLException

getDbReadStatement

protected java.sql.Statement getDbReadStatement()
                                         throws java.sql.SQLException,
                                                DbConnectionClosed

Returns:

a Statement to read the schema. If possible, an old Statement with closed ResultSet is returned. The new ResultSet of the Statement has to be registered. this is done by the executeSqlRead method.

Throws:

java.sql.SQLException

DbConnectionClosed

getDbWriteStatement

protected java.sql.Statement getDbWriteStatement()
                                          throws java.sql.SQLException,
                                                 DbConnectionClosed

Returns:

a Statement to write to the database.

Throws:

java.sql.SQLException

DbConnectionClosed

executeSqlWrite

public void executeSqlWrite(java.lang.String query)
                     throws java.sql.SQLException,
                            DbConnectionClosed

Method to comfortably write to the database. If possible automatic batching is applied.

Parameters:

query - an SQL query to be executed. This has to be a write operation to the database, or an SQL string to execute a procedure in the according schema.

Throws:

java.sql.SQLException

DbConnectionClosed

createSQLView

public void createSQLView(Columnset cs,
                          boolean materialize)
                   throws java.sql.SQLException,
                          DbConnectionClosed

Create the generated sql definition for a new view within the database, or materialize the view as a table, if this is preferrable.

Parameters:

Columnset - to be tested

stepId - the Id of the step in which this Columnset was created

Throws:

java.sql.SQLException

DbConnectionClosed

createSQLFunction

public void createSQLFunction(java.lang.String myFunction)
                       throws java.sql.SQLException,
                              DbConnectionClosed

Create a function in the database by using the given function definition.

Parameters:

myFunction - a function definition for a SQL function

Throws:

java.sql.SQLException

DbConnectionClosed

createSqlIndex

public java.lang.String createSqlIndex(java.lang.String tableName,
                                       java.lang.String[] attributes)
                                throws java.sql.SQLException,
                                       DbConnectionClosed

Creates a database index for the given table and set of attributes.

Parameters:

tableName - the table to create an index on

attributes - an array of attribute names, specifying for which attributes an index should be created

Returns:

the name of the index or null.

Throws:

java.sql.SQLException

DbConnectionClosed

executeSqlRead

public java.sql.ResultSet executeSqlRead(java.lang.String query)
                                  throws java.sql.SQLException,
                                         DbConnectionClosed

Method to comfortably read from the database.

Parameters:

query - an SQL query to be executed. This has to be a read operation on the database.

Returns:

the corresponding ResultSet

Throws:

java.sql.SQLException

DbConnectionClosed

executeSqlWrite

protected void executeSqlWrite(java.lang.String query,
                               java.sql.Statement stmt)
                        throws java.sql.SQLException

Parameters:

query - an SQL query to be executed. This has to be a write operation or an SQL string to execute a stored procedure.

stmt - the Statement to be used to execute the query

Throws:

java.sql.SQLException

executeSingleValueSqlReadL

protected java.lang.Long executeSingleValueSqlReadL(java.lang.String query,
                                                    java.sql.Statement stmt)
                                             throws java.sql.SQLException

Parameters:

query - an SQL query to be executed. This has to be a read operation yielding a single (numeric) value, which is convertable to datatype long.

stmt - the Statement to be used to execute the query

Returns:

the result as a String, or null, if no value was returned.

Throws:

java.sql.SQLException

executeSingleValueSqlReadL

public java.lang.Long executeSingleValueSqlReadL(java.lang.String query)
                                          throws java.sql.SQLException,
                                                 DbConnectionClosed

Throws:

java.sql.SQLException

DbConnectionClosed

See Also:

In contrast to that method, this method creates and then closes its own Statement.

executeSingleValueSqlRead

public java.lang.String executeSingleValueSqlRead(java.lang.String query)
                                           throws java.sql.SQLException,
                                                  DbConnectionClosed

Throws:

java.sql.SQLException

DbConnectionClosed

See Also:

In contrast to that method, this method creates and then closes its own Statement.

getNextM4SequenceValue

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

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

executeDBProcedure

public void executeDBProcedure(java.lang.String procedureName,
                               java.lang.String[] parameters)
                        throws java.sql.SQLException,
                               DbConnectionClosed,
                               M4CompilerError

Method to execute a stored procedure residing in the according schema.

Parameters:

procedureName - the name of the stored procedure in the database

parameters - the parameters to be passed to the stored procedure. In SQL code these parameters are comma separated.

Throws:

java.sql.SQLException

DbConnectionClosed

M4CompilerError

commitBatch

protected static void commitBatch(java.sql.Statement stmt)
                           throws java.sql.SQLException

commits and clears a batch

Throws:

java.sql.SQLException

getSelectStringAllTables

public abstract java.lang.String getSelectStringAllTables()

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.

Returns:

An SQL String

getSelectStringAllViews

public abstract java.lang.String getSelectStringAllViews()

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.

Returns:

An SQL String

tableExists

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

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

Parameters:

tableName - the table name

Returns:

TRUE or FALSE

Throws:

M4Exception

getSelectStringAllColumnsForDbObject

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

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.

Parameters:

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

Returns:

An SQL String

getSelectStringDistribValuesTimeColumn

public abstract 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). The given distribution base determines the granularity of aggregation. In this way daywise or monthwise values can be selected, for example.

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

getAttributeForColumnNames

public abstract java.lang.String getAttributeForColumnNames()

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

Returns:

the name of the column that contains the column names.

getAttributeForColumnTypes

public abstract java.lang.String getAttributeForColumnTypes()

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

Returns:

the name of the column that contains the column types.

getUniqueRowIdentifier

public abstract java.lang.String getUniqueRowIdentifier()

Abstract method to be implemented by the subclasses. Returns a String that can be used to uniquely identify table rows in SQL-Statements. This is DBMS-dependent.

Returns:

the unique row identifier name

getPowerExpression

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

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.

Parameters:

base -

exponent -

Returns:

a string with the power expression

getFloorExpression

public abstract 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.

Returns:

a string with the floor expression

getRoundToDecimalPlacesExpression

public abstract 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.

Returns:

a string with the rounding expression

getNumberOfMonthsBetween

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

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).

Parameters:

dbObjectName -

firstValue -

secondValue -

Returns:

Throws:

M4Exception

getAliasExpressionForInnerSelects

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

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.

Parameters:

aliasName -

Returns:

a string with the alias expression

getTablesReferencedBy

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

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.

Parameters:

dbObjectName - the given table name

Returns:

a Map whose keys and values are Strings

Throws:

java.sql.SQLException

DbConnectionClosed

getTablesReferringTo

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

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.

Parameters:

dbObjectName - the given table name

Returns:

a Map whose keys and values are Strings

Throws:

java.sql.SQLException

DbConnectionClosed

hasOnlyForeignKeyColumns

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

Returns TRUE iff the given table/view has ONLY columns that act as foreign keys to other tables.

Parameters:

dbObjectName - name of given table/view

Returns:

a boolean value

Throws:

java.sql.SQLException

DbConnectionClosed

isColumnUsedAsPrimaryKey

public boolean isColumnUsedAsPrimaryKey(java.lang.String columnName,
                                        java.lang.String dbObjectName)
                                 throws java.sql.SQLException,
                                        DbConnectionClosed

Throws:

java.sql.SQLException

DbConnectionClosed

getColumnTestQuery

public java.lang.String getColumnTestQuery(Column col)

Returns a string that can be used as a query. If the query can be executed without errors, it means that the given Column has a well-formed SQL definition.

Returns:

a query string

getPrimaryKeyColumnNames

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

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.

Parameters:

dbObjectName - the name of the given table or view

Returns:

a Collection of Strings

Throws:

java.sql.SQLException

DbConnectionClosed

getTableOrViewType

public abstract 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.

Parameters:

dbObjectName - name of a table or view

Returns:

a String with the type information

Throws:

java.sql.SQLException

DbConnectionClosed

getDatatypeName

public abstract 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.

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.

getM4DatatypeName

public abstract 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.

Parameters:

dbmsDatatypeName - the name of the datatype in the underlying DBMS

Returns:

the corresponding M4 Relational Datatype

getSelectStringColumnDataTypes

public abstract 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).

Parameters:

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

owner - Name of the owner of the table or view

columnName - Name of the column whose datatype is returned

Returns:

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

dropRelation

public abstract 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.

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 abstract java.lang.String getTestQuery()

Returns:

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

createPrimaryKeyConstraint

public abstract java.lang.String createPrimaryKeyConstraint(java.lang.String tableName,
                                                            java.util.Collection pkAttributeNames,
                                                            java.lang.String dbConstraintName)
                                                     throws java.sql.SQLException,
                                                            M4CompilerError

Creates a primary key constraint in the database.

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

M4CompilerError

createForeignKeyConstraint

public abstract 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,
                                                M4CompilerError

This method creates a foreign key constraint in the database.

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

M4CompilerError

stringCollectionToCommaSeparated

public static java.lang.String stringCollectionToCommaSeparated(java.util.Collection col)

Helper method, turns collections of strings into comma separated strings.