com.j256.ormlite.db
Interface DatabaseType

All Known Implementing Classes:

BaseDatabaseType, Db2DatabaseType, DerbyClientServerDatabaseType, DerbyEmbeddedDatabaseType, H2DatabaseType, HsqldbDatabaseType, MysqlDatabaseType, OracleDatabaseType, PostgresDatabaseType, SqlDroidDatabaseType, SqliteAndroidDatabaseType, SqliteDatabaseType, SqlServerDatabaseType, SqlServerJtdsDatabaseType

public interface DatabaseType

Definition of the per-database functionality needed to isolate the differences between the various databases.

Author:

graywatson

Method Summary

void	appendColumnArg(StringBuilder sb, FieldType fieldType, List<String> additionalArgs, List<String> statementsBefore, List<String> statementsAfter, List<String> queriesAfter) Takes a FieldType and appends the SQL necessary to create the field to the string builder.
void	appendCreateTableSuffix(StringBuilder sb) Append the SQL necessary to properly finish a CREATE TABLE line.
void	appendEscapedEntityName(StringBuilder sb, String word) Add a entity-name word to the string builder wrapped in the proper characters to escape it.
void	appendEscapedWord(StringBuilder sb, String word) Add the word to the string builder wrapped in the proper characters to escape it.
void	appendLimitValue(StringBuilder sb, int limit) Append to the string builder the necessary SQL to limit the results to a certain number.
void	appendSelectNextValFromSequence(StringBuilder sb, String sequenceName) Append the SQL necessary to get the next-value from a sequence.
DatabaseAccess	buildDatabaseAccess(DataSource dataSource) Return a newly built database access object which possibly is attached to the provided data source.
String	convertColumnName(String columnName) Convert and return the column name for table and sequence creation.
void	dropColumnArg(FieldType fieldType, List<String> statementsBefore, List<String> statementsAfter) Takes a FieldType and adds the necessary statements to the before and after lists necessary so that the dropping of the table will succeed and will clear other associated sequences or other database artifacts
String	generateIdSequenceName(String tableName, FieldType idFieldType) Return the name of an ID sequence based on the tabelName and the fieldType of the id.
String	getCommentLinePrefix() Return the prefix to put at the front of a SQL line to mark it as a comment.
String	getDriverClassName() Return the class name of the database driver.
String	getDriverUrlPart() Return the part in the database URI which identifies the particular database.
FieldConverter	getFieldConverter(FieldType fieldType) Return the FieldConverter to associate with the FieldType.
boolean	isCreateTableReturnsZero() Returns true if a 'CREATE TABLE' statement should return 0.
boolean	isEntityNamesMustBeUpCase() Returns true if table and field names should be made uppercase.
boolean	isIdSequenceNeeded() Return true if the database needs a sequence when you use generated IDs.
boolean	isLimitAfterSelect() Return true if the LIMIT should be called after SELECT otherwise at the end of the WHERE (the default).
boolean	isLimitSqlSupported() Return true if the database supports the LIMIT SQL command.
boolean	isVarcharFieldWidthSupported() Return true if the database supports the width parameter on VARCHAR fields.
void	loadDriver() Load the driver class associated with this database so it can wire itself into JDBC.

Method Detail

getDriverUrlPart

String getDriverUrlPart()

Return the part in the database URI which identifies the particular database. Usually the URI is in the form jdbc:ddd:... where ddd is the driver url part.

getDriverClassName

String getDriverClassName()

Return the class name of the database driver.

buildDatabaseAccess

DatabaseAccess buildDatabaseAccess(DataSource dataSource)

Return a newly built database access object which possibly is attached to the provided data source. Returns null if the dataSource was not set and it is required.

loadDriver

void loadDriver()
                throws ClassNotFoundException

Load the driver class associated with this database so it can wire itself into JDBC.

Throws:

ClassNotFoundException - If the driver class is not available in the classpath.

appendColumnArg

void appendColumnArg(StringBuilder sb,
                     FieldType fieldType,
                     List<String> additionalArgs,
                     List<String> statementsBefore,
                     List<String> statementsAfter,
                     List<String> queriesAfter)

Takes a FieldType and appends the SQL necessary to create the field to the string builder. The field may also generate additional arguments which go at the end of the insert statement or additional statements to be executed before or afterwards depending on the configurations. The database can also add to the list of queries that will be performed afterward to test portions of the config.

convertColumnName

String convertColumnName(String columnName)

Convert and return the column name for table and sequence creation. Often this is necessary to fix case issues.

dropColumnArg

void dropColumnArg(FieldType fieldType,
                   List<String> statementsBefore,
                   List<String> statementsAfter)

Takes a FieldType and adds the necessary statements to the before and after lists necessary so that the dropping of the table will succeed and will clear other associated sequences or other database artifacts

appendEscapedEntityName

void appendEscapedEntityName(StringBuilder sb,
                             String word)

Add a entity-name word to the string builder wrapped in the proper characters to escape it. This avoids problems with table, column, and sequence-names being reserved words.

appendEscapedWord

void appendEscapedWord(StringBuilder sb,
                       String word)

Add the word to the string builder wrapped in the proper characters to escape it. This avoids problems with data values being reserved words.

generateIdSequenceName

String generateIdSequenceName(String tableName,
                              FieldType idFieldType)

Return the name of an ID sequence based on the tabelName and the fieldType of the id.

getCommentLinePrefix

String getCommentLinePrefix()

Return the prefix to put at the front of a SQL line to mark it as a comment.

isIdSequenceNeeded

boolean isIdSequenceNeeded()

Return true if the database needs a sequence when you use generated IDs. Some databases (H2, MySQL) create them auto-magically. This also means that the database needs to query for a sequence value before the object is inserted. For old[er] versions of Postgres, for example, the JDBC call-back stuff to get the just-inserted id value does not work so we have to get the next sequence value by hand, assign it into the object, and then insert the object -- yes two SQL statements.

getFieldConverter

FieldConverter getFieldConverter(FieldType fieldType)

Return the FieldConverter to associate with the FieldType. This allows the database instance to convert a field as necessary before it goes to the database.

isVarcharFieldWidthSupported

boolean isVarcharFieldWidthSupported()

Return true if the database supports the width parameter on VARCHAR fields.

isLimitSqlSupported

boolean isLimitSqlSupported()

Return true if the database supports the LIMIT SQL command. Otherwise we have to use the Statement.setMaxRows(int) instead. See prepareSqlStatement in MappedPreparedQuery.

isLimitAfterSelect

boolean isLimitAfterSelect()

Return true if the LIMIT should be called after SELECT otherwise at the end of the WHERE (the default).

appendLimitValue

void appendLimitValue(StringBuilder sb,
                      int limit)

Append to the string builder the necessary SQL to limit the results to a certain number.

appendSelectNextValFromSequence

void appendSelectNextValFromSequence(StringBuilder sb,
                                     String sequenceName)

Append the SQL necessary to get the next-value from a sequence. This is only necessary if isIdSequenceNeeded() is true.

appendCreateTableSuffix

void appendCreateTableSuffix(StringBuilder sb)

Append the SQL necessary to properly finish a CREATE TABLE line.

isCreateTableReturnsZero

boolean isCreateTableReturnsZero()

Returns true if a 'CREATE TABLE' statement should return 0. False if > 0.

isEntityNamesMustBeUpCase

boolean isEntityNamesMustBeUpCase()

Returns true if table and field names should be made uppercase.

Turns out that Derby and Hsqldb are doing something wrong (IMO) with entity names. If you create a table with the name "footable" (with the quotes) then it will be created as lowercase footable, case sensitive. However, if you then issue the query 'select * from footable' it won't find the table because it gets promoted to be FOOTABLE and is searched in a case sensitive manner. So for these databases, entity names have to be forced to be uppercase so external queries will also work.