net.java.ao.db
Class MySQLDatabaseProvider

java.lang.Object
  net.java.ao.DatabaseProvider
      net.java.ao.db.MySQLDatabaseProvider

public final class MySQLDatabaseProvider
extends DatabaseProvider

Author:

Daniel Spiewak

Nested Class Summary

Nested classes/interfaces inherited from class net.java.ao.DatabaseProvider

DatabaseProvider.RenderFieldOptions, DatabaseProvider.SqlListener

Field Summary

Fields inherited from class net.java.ao.DatabaseProvider

logger, sqlLogger, typeManager

Constructor Summary

MySQLDatabaseProvider(DisposableDataSource dataSource)

Method Summary

protected boolean	considerPrecision(DDLField field) Determines whether or not the database allows explicit precisions for the field in question.
protected String	convertTypeToString(DatabaseType<?> type) Converts the specified type into the database-specific DDL String value.
protected Set<String>	getReservedWords() Retrieves the set of all reserved words for the underlying database.
boolean	isCaseSensetive() Flag indicating whether or not the underlying database uses case-sensetive identifiers.
protected List<String>	renderAlterTableAddColumn(NameConverters nameConverters, DDLTable table, DDLField field) Generates the database-specific DDL statements required to add a column to an existing table.
protected List<String>	renderAlterTableChangeColumn(NameConverters nameConverters, DDLTable table, DDLField oldField, DDLField field) Generates the database-specific DDL statements required to change the given column from its old specification to the given DDL value.
protected String	renderAppend() Generates any database-specific options which must be appended to the end of a table definition.
protected String	renderAutoIncrement() Generates the DDL fragment required to specify an INTEGER field as auto-incremented.
protected String	renderConstraintsForTable(UniqueNameConverter uniqueNameConverter, DDLTable table) Renders the foreign key constraints in database-specific DDL for the table in question.
protected String	renderCreateIndex(IndexNameConverter indexNameConverter, DDLIndex index) Generates the database-specific DDL statement required to create a new index.
protected String	renderFieldType(DDLField field) Renders the database-specific DDL type for the field in question.
protected String	renderUnique(UniqueNameConverter uniqueNameConverter, DDLTable table, DDLField field) Renders the UNIQUE constraint as defined by the database-specific DDL syntax.

Methods inherited from class net.java.ao.DatabaseProvider

addSqlListener, commitTransaction, dispose, executeInsertReturningKey, executeUpdate, getConnection, getDateFormat, getFunctionNameForField, getImportedKeys, getIndexes, getMaxIDLength, getSchema, getSequences, getTables, getTriggerNameForField, getTypeManager, handleBlob, handleUpdateError, insertReturningKey, isNumericType, isSchemaNotEmpty, onSql, parseValue, preparedStatement, preparedStatement, preparedStatement, processID, processOnClause, processWhereClause, putBoolean, putNull, quote, removeSqlListener, renderAction, renderAlterTableAddKey, renderAlterTableChangeColumnStatement, renderAlterTableDropColumn, renderAlterTableDropKey, renderCalendar, renderDropFunctions, renderDropIndex, renderDropSequences, renderDropTable, renderDropTriggers, renderField, renderFieldDefault, renderFieldOptionsInAlterColumn, renderFieldPrecision, renderFields, renderForeignKey, renderFunction, renderFunctionForField, renderFunctions, renderInsert, renderOnUpdate, renderQuery, renderQueryGroupBy, renderQueryJoins, renderQueryLimit, renderQueryOrderBy, renderQuerySelect, renderQueryWhere, renderSequences, renderTable, renderTriggerForField, renderTriggers, renderValue, rollbackTransaction, setPostConnectionProperties, setQueryResultSetProperties, setQueryStatementProperties, shorten, shouldQuoteID, startTransaction, withSchema

Methods inherited from class java.lang.Object

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

Constructor Detail

MySQLDatabaseProvider

public MySQLDatabaseProvider(DisposableDataSource dataSource)

Method Detail

considerPrecision

protected boolean considerPrecision(DDLField field)

Description copied from class: DatabaseProvider

Determines whether or not the database allows explicit precisions for the field in question. This is to support databases such as Derby which do not support precisions for certain types. By default, this method returns true.

More often than not, all that is required for this determination is the type. As such, the method signature may change in a future release.

Overrides:

considerPrecision in class DatabaseProvider

Parameters:

field - The field for which precision should/shouldn't be rendered.

Returns:

true if precision should be rendered, otherwise false.

convertTypeToString

protected String convertTypeToString(DatabaseType<?> type)

Description copied from class: DatabaseProvider

Converts the specified type into the database-specific DDL String value. By default, this delegates to the DatabaseType#getDefaultName() method. Subclass implementations should be sure to make a super call in order to ensure that both default naming and future special cases are handled appropriately.

Overrides:

convertTypeToString in class DatabaseProvider

Parameters:

type - The type instance to convert to a DDL string.

Returns:

The database-specific DDL representation of the type (e.g. "VARCHAR").

See Also:

DatabaseType.getDefaultName()

renderAutoIncrement

protected String renderAutoIncrement()

Description copied from class: DatabaseProvider

Generates the DDL fragment required to specify an INTEGER field as auto-incremented. For databases which do not support such flags (which is just about every database exception MySQL), "" is an acceptable return value. This method should never return null as it would cause the field rendering method to throw a NullPointerException.

Overrides:

renderAutoIncrement in class DatabaseProvider

renderAppend

protected String renderAppend()

Description copied from class: DatabaseProvider

Generates any database-specific options which must be appended to the end of a table definition. The only database I am aware of which requires this is MySQL. For example:

CREATE TABLE test (
     id INTEGER NOT NULL AUTO_INCREMENT,
     name VARCHAR(45),
     PRIMARY KEY(id)
 ) ENGINE=InnoDB;

The "ENGINE=InnoDB" clause is what is returned by this method. The default implementation simply returns null, signifying that no append should be rendered.

Overrides:

renderAppend in class DatabaseProvider

Returns:

A DDL clause to be appended to the CREATE TABLE DDL, or null

renderUnique

protected String renderUnique(UniqueNameConverter uniqueNameConverter,
                              DDLTable table,
                              DDLField field)

Description copied from class: DatabaseProvider

Renders the UNIQUE constraint as defined by the database-specific DDL syntax. This method is a delegate of other, more complex methods such as DatabaseProvider.renderField(net.java.ao.schema.NameConverters, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField, net.java.ao.DatabaseProvider.RenderFieldOptions). The default implementation just returns UNIQUE. Implementations may override this method to return an empty String if the database in question does not support the constraint.

Overrides:

renderUnique in class DatabaseProvider

Returns:

The database-specific rendering of UNIQUE.

renderConstraintsForTable

protected String renderConstraintsForTable(UniqueNameConverter uniqueNameConverter,
                                           DDLTable table)

Description copied from class: DatabaseProvider

Renders the foreign key constraints in database-specific DDL for the table in question. Actually, this method only loops through the foreign keys and renders indentation and line-breaks. The actual rendering is done in a second delegate method.

Overrides:

renderConstraintsForTable in class DatabaseProvider

table - The database-agnostic DDL representation of the table in question.

Returns:

The String rendering of all of the foreign keys for the table.

See Also:

DatabaseProvider.renderForeignKey(DDLForeignKey)

renderAlterTableAddColumn

protected List<String> renderAlterTableAddColumn(NameConverters nameConverters,
                                                 DDLTable table,
                                                 DDLField field)

Description copied from class: DatabaseProvider

Generates the database-specific DDL statements required to add a column to an existing table. Included in the return value should be the statements required to add all necessary functions and triggers to ensure that the column acts appropriately. For example, if the field is tagged with an @OnUpdate annotation, chances are there will be a trigger and possibly a function along with the ALTER statement. These "extra" functions are properly ordered and will only be appended if their values are not null. Because of this, very few database providers will need to override this method.

Overrides:

renderAlterTableAddColumn in class DatabaseProvider

table - The table which should receive the new column.

field - The column to add to the specified table. @return An array of DDL statements to execute.

See Also:

DatabaseProvider.renderFunctionForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField), DatabaseProvider.renderTriggerForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.SequenceNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField)

renderAlterTableChangeColumn

protected List<String> renderAlterTableChangeColumn(NameConverters nameConverters,
                                                    DDLTable table,
                                                    DDLField oldField,
                                                    DDLField field)

Description copied from class: DatabaseProvider

Generates the database-specific DDL statements required to change the given column from its old specification to the given DDL value. This method will also generate the appropriate statements to remove old triggers and functions, as well as add new ones according to the requirements of the new field definition.

The default implementation of this method functions in the manner specified by the MySQL database. Some databases will have to perform more complicated actions (such as dropping and re-adding the field) in order to satesfy the same use-case. Such databases should print a warning to stderr to ensure that the end-developer is aware of such restrictions.

Thus, the specification for this method allows for data loss. Nevertheless, if the database supplies a mechanism to accomplish the task without data loss, it should be applied.

For maximum flexibility, the default implementation of this method only deals with the dropping and addition of functions and triggers. The actual generation of the ALTER TABLE statement is done in the DatabaseProvider.renderAlterTableChangeColumnStatement(net.java.ao.schema.NameConverters, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField, net.java.ao.schema.ddl.DDLField, net.java.ao.DatabaseProvider.RenderFieldOptions) method.

Overrides:

renderAlterTableChangeColumn in class DatabaseProvider

table - The table containing the column to change.

oldField - The old column definition.

field - The new column definition (defining the resultant DDL). @return An array of DDL statements to be executed.

See Also:

DatabaseProvider.getTriggerNameForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField), DatabaseProvider.getFunctionNameForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField), DatabaseProvider.renderFunctionForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField), DatabaseProvider.renderTriggerForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.SequenceNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField)

renderFieldType

protected String renderFieldType(DDLField field)

Description copied from class: DatabaseProvider

Renders the database-specific DDL type for the field in question. This method merely delegates to the DatabaseProvider.convertTypeToString(DatabaseType) method, passing the field type. Thus, it is rarely necessary (if ever) to override this method. It may be deprecated in a future release.

Overrides:

renderFieldType in class DatabaseProvider

Parameters:

field - The field which contains the type to be rendered.

Returns:

The database-specific type DDL rendering.

renderCreateIndex

protected String renderCreateIndex(IndexNameConverter indexNameConverter,
                                   DDLIndex index)

Description copied from class: DatabaseProvider

Generates the database-specific DDL statement required to create a new index. The syntax for this operation is highly standardized and thus it is unlikely this method will be overridden. If the database in question does not support indexes, a warning should be printed to stderr and null returned.

Overrides:

renderCreateIndex in class DatabaseProvider

index - The index to create. This single instance contains all of the data necessary to create the index, thus no separate parameters (such as a DDLTable) are required.

Returns:

A DDL statement to be executed, or null.

getReservedWords

protected Set<String> getReservedWords()

Description copied from class: DatabaseProvider

Retrieves the set of all reserved words for the underlying database. The set returns should be speculative, meaning that it should include any possible reserved words, not just those for a particular version. As an implementation guideline, the Set instance returned from this method should guarentee O(1) lookup times, otherwise ORM performance will suffer greatly.

Specified by:

getReservedWords in class DatabaseProvider

Returns:

A set of upper case reserved words specific to the database.

isCaseSensetive

public boolean isCaseSensetive()

Description copied from class: DatabaseProvider

Flag indicating whether or not the underlying database uses case-sensetive identifiers. This specifically affects comparisons in the SchemaReader utility. The default value is true. Note that databases which support both case-sensetive and case-insensetive identifiers (like MySQL) should return true for better all-around compatibility.

Overrides:

isCaseSensetive in class DatabaseProvider

Returns:

boolean true if identifiers are case-sensetive, false otherwise.