org.datanucleus.store.rdbms.adapter
Class DB2Adapter

java.lang.Object
  org.datanucleus.store.rdbms.adapter.DatabaseAdapter
      org.datanucleus.store.rdbms.adapter.DB2Adapter

All Implemented Interfaces:

org.datanucleus.store.mapped.DatastoreAdapter, org.datanucleus.store.mapped.expression.ExpressionConversionAdapter, org.datanucleus.store.mapped.expression.ExpressionLogicSetAdapter, org.datanucleus.store.mapped.expression.ExpressionMethodAdapter, org.datanucleus.store.mapped.expression.ExpressionOperatorAdapter, org.datanucleus.store.mapped.expression.ExpressionPatternAdapter, RDBMSAdapter

Direct Known Subclasses:

DB2AS400Adapter

public class DB2Adapter
extends DatabaseAdapter

Provides methods for adapting SQL language elements to the DB2 database.

See Also:

DatabaseAdapter

Field Summary

static java.lang.String

DB2_RESERVED_WORDS A string containing the list of DB2 keywords This list is normally obtained dynamically from the driver using DatabaseMetaData.getSQLKeywords() Based on database DB2 version 7

Fields inherited from class org.datanucleus.store.rdbms.adapter.DatabaseAdapter

catalogSeparator, datastoreMajorVersion, datastoreMinorVersion, datastoreProductName, datastoreProductVersion, datastoreRevisionVersion, driverMajorVersion, driverMinorVersion, driverName, driverVersion, identifierQuoteString, LOCALISER, LOCALISER_BASE, maxColumnNameLength, maxConstraintNameLength, maxIndexNameLength, maxTableNameLength, properties, reservedKeywords, supportedOptions

Fields inherited from interface org.datanucleus.store.rdbms.adapter.RDBMSAdapter

ACCESS_PARENTQUERY_IN_SUBQUERY, ALTER_TABLE_DROP_CONSTRAINT_SYNTAX, ALTER_TABLE_DROP_FOREIGN_KEY_CONSTRAINT, ANSI_JOIN_SYNTAX, AUTO_INCREMENT_COLUMN_TYPE_SPECIFICATION, AUTO_INCREMENT_KEYS_NULL_SPECIFICATION, BLOB_SET_USING_SETSTRING, CHAR_COLUMNS_PADDED_WITH_SPACES, CHECK_IN_CREATE_STATEMENTS, CHECK_IN_END_CREATE_STATEMENTS, CLOB_SET_USING_SETSTRING, CREATE_INDEXES_BEFORE_FOREIGN_KEYS, DATETIME_STORES_MILLISECS, DEFAULT_BEFORE_NULL_IN_COLUMN_OPTIONS, DEFAULT_KEYWORD_IN_COLUMN_OPTIONS, DEFAULT_KEYWORD_WITH_NOT_NULL_IN_COLUMN_OPTIONS, DEFERRED_CONSTRAINTS, DISTINCT_WITH_SELECT_FOR_UPDATE, EXISTS_SYNTAX, FK_DELETE_ACTION_CASCADE, FK_DELETE_ACTION_DEFAULT, FK_DELETE_ACTION_NULL, FK_DELETE_ACTION_RESTRICT, FK_UPDATE_ACTION_CASCADE, FK_UPDATE_ACTION_DEFAULT, FK_UPDATE_ACTION_NULL, FK_UPDATE_ACTION_RESTRICT, GET_GENERATED_KEYS_STATEMENT, INCLUDE_ORDERBY_COLS_IN_SELECT, LOCK_OPTION_PLACED_AFTER_FROM, LOCK_OPTION_PLACED_WITHIN_JOIN, LOCK_WITH_SELECT_FOR_UPDATE, NULL_EQUALS_EMPTY_STRING, NULLS_IN_CANDIDATE_KEYS, NULLS_KEYWORD_IN_COLUMN_OPTIONS, ORDERBY_USING_SELECT_COLUMN_INDEX, PERSIST_OF_UNASSIGNED_CHAR, PRIMARYKEY_IN_CREATE_STATEMENTS, STATEMENT_BATCHING, TX_ISOLATION_NONE, TX_ISOLATION_READ_COMMITTED, TX_ISOLATION_READ_UNCOMMITTED, TX_ISOLATION_REPEATABLE_READ, TX_ISOLATION_SERIALIZABLE, UNION_SYNTAX, UNIQUE_IN_END_CREATE_STATEMENTS, USE_UNION_ALL, VIEWS

Fields inherited from interface org.datanucleus.store.mapped.DatastoreAdapter

ANALYSIS_METHODS, BIT_IS_REALLY_BOOLEAN, BOOLEAN_COMPARISON, CATALOGS_IN_TABLE_DEFINITIONS, ESCAPE_EXPRESSION_IN_LIKE_PREDICATE, IDENTIFIERS_LOWERCASE, IDENTIFIERS_LOWERCASE_QUOTED, IDENTIFIERS_MIXEDCASE, IDENTIFIERS_MIXEDCASE_QUOTED, IDENTIFIERS_MIXEDCASE_QUOTED_SENSITIVE, IDENTIFIERS_MIXEDCASE_SENSITIVE, IDENTIFIERS_UPPERCASE, IDENTIFIERS_UPPERCASE_QUOTED, IDENTITY_COLUMNS, PROJECTION_IN_TABLE_REFERENCE_JOINS, SCHEMAS_IN_TABLE_DEFINITIONS, SEQUENCES

Constructor Summary

DB2Adapter(java.sql.DatabaseMetaData metadata)
Constructs a DB2 adapter based on the given JDBC metadata.

Method Summary

org.datanucleus.store.mapped.expression.ScalarExpression	concatOperator(org.datanucleus.store.mapped.expression.ScalarExpression operand1, org.datanucleus.store.mapped.expression.ScalarExpression operand2) If only one operand expression is of type String, then string conversion is performed on the other operand to produce a string at run time.
org.datanucleus.store.mapped.expression.BooleanExpression	endsWithMethod(org.datanucleus.store.mapped.expression.ScalarExpression leftOperand, org.datanucleus.store.mapped.expression.ScalarExpression rightOperand) Returns whether this string ends with the specified string.
java.lang.String	getAutoIncrementKeyword() Accessor for the auto-increment keyword for generating DDLs (CREATE TABLEs...).
java.lang.String	getAutoIncrementStmt(Table table, java.lang.String columnName) Accessor for the auto-increment sql statement for this datastore.
java.lang.String	getContinuationString() Continuation string to use where the SQL statement goes over more than 1 line.
int	getDatastoreIdentifierMaxLength(org.datanucleus.store.mapped.IdentifierType identifierType) Method to return the maximum length of a datastore identifier of the specified type.
java.lang.String	getDropTableStatement(org.datanucleus.store.mapped.DatastoreContainerObject table) Returns the appropriate SQL to drop the given table.
org.datanucleus.store.mapped.expression.NumericExpression	getNumericExpressionForMethod(java.lang.String method, org.datanucleus.store.mapped.expression.ScalarExpression expr) Accessor for a numeric expression to represent the method call, with passed argument.
java.lang.String	getSchemaName(java.sql.Connection conn) Accessor for the Schema Name for this datastore.
java.lang.String	getSequenceCreateStmt(java.lang.String sequence_name, java.lang.String min, java.lang.String max, java.lang.String start, java.lang.String increment, java.lang.String cache_size) Accessor for the sequence statement to create the sequence.
java.lang.String	getSequenceNextStmt(java.lang.String sequence_name) Accessor for the statement for getting the next id from the sequence for this datastore.
int	getUnlimitedLengthPrecisionValue(SQLTypeInfo typeInfo) Returns the precision value to be used when creating string columns of "unlimited" length.
java.lang.String	getVendorID()
org.datanucleus.store.mapped.expression.NumericExpression	indexOfMethod(org.datanucleus.store.mapped.expression.ScalarExpression source, org.datanucleus.store.mapped.expression.ScalarExpression str, org.datanucleus.store.mapped.expression.NumericExpression from) Returns the appropriate SQL expression for the JDOQL String.indexOf() method.
void	initialiseTypes(org.datanucleus.store.schema.StoreSchemaHandler handler, org.datanucleus.ManagedConnection mconn) Initialise the types for this datastore.
org.datanucleus.store.mapped.expression.NumericExpression	modOperator(org.datanucleus.store.mapped.expression.ScalarExpression operand1, org.datanucleus.store.mapped.expression.ScalarExpression operand2) Method to generate a modulus expression.
RDBMSColumnInfo	newRDBMSColumnInfo(java.sql.ResultSet rs) Method to create a column info for the current row.
SQLTypeInfo	newSQLTypeInfo(java.sql.ResultSet rs) Create a new SQL type info from the current row of the passed ResultSet.
org.datanucleus.store.mapped.expression.LogicSetExpression	newTableExpression(org.datanucleus.store.mapped.expression.QueryExpression qs, org.datanucleus.store.mapped.DatastoreContainerObject table, org.datanucleus.store.mapped.DatastoreIdentifier rangeVar) Returns a new TableExpression object appropriate for this DBMS.
org.datanucleus.store.mapped.expression.BooleanExpression	startsWithMethod(org.datanucleus.store.mapped.expression.ScalarExpression source, org.datanucleus.store.mapped.expression.ScalarExpression str) Method to handle the starts with operation.
org.datanucleus.store.mapped.expression.StringExpression	substringMethod(org.datanucleus.store.mapped.expression.StringExpression str, org.datanucleus.store.mapped.expression.NumericExpression begin) Returns the appropriate SQL expression for the JDOQL String.substring(str,begin) method.
org.datanucleus.store.mapped.expression.StringExpression	substringMethod(org.datanucleus.store.mapped.expression.StringExpression str, org.datanucleus.store.mapped.expression.NumericExpression begin, org.datanucleus.store.mapped.expression.NumericExpression end) Returns the appropriate SQL expression for the JDOQL String.substring(str,begin,end) method.
org.datanucleus.store.mapped.expression.StringExpression	toStringExpression(org.datanucleus.store.mapped.expression.StringLiteral expr) A String conversion that converts a String literal to String expression.
org.datanucleus.store.mapped.expression.StringExpression	translateMethod(org.datanucleus.store.mapped.expression.ScalarExpression expr, org.datanucleus.store.mapped.expression.ScalarExpression toExpr, org.datanucleus.store.mapped.expression.ScalarExpression fromExpr) Method to translate all chars in this expression to the fromExpr which corresponds to toExpr.
org.datanucleus.store.mapped.expression.StringExpression	trimMethod(org.datanucleus.store.mapped.expression.StringExpression str, boolean leading, boolean trailing) Returns the appropriate SQL expression for the java query "trim" method.

Methods inherited from class org.datanucleus.store.rdbms.adapter.DatabaseAdapter

addSQLTypeForJDBCType, cartersianProduct, getAdapterTime, getAddCandidateKeyStatement, getAddColumnStatement, getAddForeignKeyStatement, getAddPrimaryKeyStatement, getCatalogName, getCatalogSeparator, getCheckConstraintForValues, getColumns, getConnection, getCreateIndexStatement, getCreateTableStatement, getCurrentDateMethod, getCurrentTimeMethod, getCurrentTimestampMethod, getDatastoreDateStatement, getDatastoreMajorVersion, getDatastoreMinorVersion, getDriverMajorVersion, getDriverMinorVersion, getDropViewStatement, getEscapeCharacter, getEscapedPatternExpression, getEscapePatternExpression, getExistingIndexes, getIdentifierQuoteString, getInsertStatementForNoColumns, getMapping, getMappingManager, getMaxForeignKeys, getMaxIndexes, getMiliseconds, getNewUUIDFunction, getNonAnsiInnerJoinWhereClause, getNonAnsiLeftOuterJoinWhereClause, getNonAnsiRightOuterJoinWhereClause, getNumericConversionFunction, getOperatorConcat, getPatternExpressionAnyCharacter, getPatternExpressionZeroMoreCharacters, getRangeByLimitSelectClause, getRangeByLimitWhereClause, getRangeByRowNumberColumn, getRequiredTransactionIsolationLevel, getSelectForUpdateText, getSelectNewUUIDStmt, getSelectWithLockOption, getSupportedOptions, getSurrogateForEmptyStrings, getTime, getTransactionIsolationForSchemaCreation, getValueForProperty, initialiseDatastore, isIdentityFieldDataType, isKeyword, isReservedKeyword, isValidPrimaryKeyType, iteratorReservedWords, logConfiguration, lowerMethod, matchesMethod, newFKInfo, newQueryStatement, parseKeywordList, removeUnsupportedMappings, setProperties, supportsOption, supportsQueryFetchSize, supportsTransactionIsolation, toNumericExpression, toString, toStringExpression, upperMethod

Methods inherited from class java.lang.Object

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

Field Detail

DB2_RESERVED_WORDS

public static final java.lang.String DB2_RESERVED_WORDS

A string containing the list of DB2 keywords This list is normally obtained dynamically from the driver using DatabaseMetaData.getSQLKeywords() Based on database DB2 version 7

See Also:

Constant Field Values

Constructor Detail

DB2Adapter

public DB2Adapter(java.sql.DatabaseMetaData metadata)

Constructs a DB2 adapter based on the given JDBC metadata.

Parameters:

metadata - the database metadata.

Method Detail

initialiseTypes

public void initialiseTypes(org.datanucleus.store.schema.StoreSchemaHandler handler,
                            org.datanucleus.ManagedConnection mconn)

Initialise the types for this datastore.

Specified by:

initialiseTypes in interface org.datanucleus.store.mapped.DatastoreAdapter

Overrides:

initialiseTypes in class DatabaseAdapter

Parameters:

handler - SchemaHandler that we initialise the types for

mconn - Managed connection to use

getVendorID

public java.lang.String getVendorID()

Specified by:

getVendorID in interface org.datanucleus.store.mapped.DatastoreAdapter

Overrides:

getVendorID in class DatabaseAdapter

getSchemaName

public java.lang.String getSchemaName(java.sql.Connection conn)
                               throws java.sql.SQLException

Description copied from class: DatabaseAdapter

Accessor for the Schema Name for this datastore.

Specified by:

getSchemaName in interface RDBMSAdapter

Overrides:

getSchemaName in class DatabaseAdapter

Parameters:

conn - Connection to the datastore

Returns:

The schema name

Throws:

java.sql.SQLException - Thrown if error occurs in determining the schema name.

getDatastoreIdentifierMaxLength

public int getDatastoreIdentifierMaxLength(org.datanucleus.store.mapped.IdentifierType identifierType)

Method to return the maximum length of a datastore identifier of the specified type. If no limit exists then returns -1

Specified by:

getDatastoreIdentifierMaxLength in interface org.datanucleus.store.mapped.DatastoreAdapter

Overrides:

getDatastoreIdentifierMaxLength in class DatabaseAdapter

Parameters:

identifierType - Type of identifier (see IdentifierFactory.TABLE, etc)

Returns:

The max permitted length of this type of identifier

newSQLTypeInfo

public SQLTypeInfo newSQLTypeInfo(java.sql.ResultSet rs)

Description copied from interface: RDBMSAdapter

Create a new SQL type info from the current row of the passed ResultSet. Allows an adapter to override particular types where the JDBC driver is known to be buggy.

Specified by:

newSQLTypeInfo in interface RDBMSAdapter

Overrides:

newSQLTypeInfo in class DatabaseAdapter

Parameters:

rs - ResultSet

Returns:

The SQL type info

newRDBMSColumnInfo

public RDBMSColumnInfo newRDBMSColumnInfo(java.sql.ResultSet rs)

Method to create a column info for the current row. Overrides the dataType/columnSize/decimalDigits to cater for DB2 particularities.

Specified by:

newRDBMSColumnInfo in interface RDBMSAdapter

Overrides:

newRDBMSColumnInfo in class DatabaseAdapter

Parameters:

rs - ResultSet from DatabaseMetaData.getColumns()

Returns:

column info

getUnlimitedLengthPrecisionValue

public int getUnlimitedLengthPrecisionValue(SQLTypeInfo typeInfo)

Description copied from class: DatabaseAdapter

Returns the precision value to be used when creating string columns of "unlimited" length. Usually, if this value is needed it is provided in. However, for some types in some databases the value must be computed.

Specified by:

getUnlimitedLengthPrecisionValue in interface RDBMSAdapter

Overrides:

getUnlimitedLengthPrecisionValue in class DatabaseAdapter

Parameters:

typeInfo - the typeInfo object for which the precision value is needed.

Returns:

the precision value to be used when creating the column, or -1 if no value should be used.

getDropTableStatement

public java.lang.String getDropTableStatement(org.datanucleus.store.mapped.DatastoreContainerObject table)

Description copied from class: DatabaseAdapter

Returns the appropriate SQL to drop the given table. It should return something like:

 DROP TABLE FOO CASCADE
 

Specified by:

getDropTableStatement in interface RDBMSAdapter

Overrides:

getDropTableStatement in class DatabaseAdapter

Parameters:

table - The table to drop.

Returns:

The text of the SQL statement.

getAutoIncrementStmt

public java.lang.String getAutoIncrementStmt(Table table,
                                             java.lang.String columnName)

Accessor for the auto-increment sql statement for this datastore.

Specified by:

getAutoIncrementStmt in interface RDBMSAdapter

Overrides:

getAutoIncrementStmt in class DatabaseAdapter

Parameters:

table - Name of the table that the autoincrement is for

columnName - Name of the column that the autoincrement is for

Returns:

The statement for getting the latest auto-increment key

getAutoIncrementKeyword

public java.lang.String getAutoIncrementKeyword()

Accessor for the auto-increment keyword for generating DDLs (CREATE TABLEs...).

Specified by:

getAutoIncrementKeyword in interface RDBMSAdapter

Overrides:

getAutoIncrementKeyword in class DatabaseAdapter

Returns:

The keyword for a column using auto-increment

getContinuationString

public java.lang.String getContinuationString()

Continuation string to use where the SQL statement goes over more than 1 line. DB2 doesn't convert newlines into continuation characters and so we just provide a space so that it accepts the statement.

Overrides:

getContinuationString in class DatabaseAdapter

Returns:

Continuation string.

getSequenceCreateStmt

public java.lang.String getSequenceCreateStmt(java.lang.String sequence_name,
                                              java.lang.String min,
                                              java.lang.String max,
                                              java.lang.String start,
                                              java.lang.String increment,
                                              java.lang.String cache_size)

Accessor for the sequence statement to create the sequence.

Specified by:

getSequenceCreateStmt in interface RDBMSAdapter

Overrides:

getSequenceCreateStmt in class DatabaseAdapter

Parameters:

sequence_name - Name of the sequence

min - Minimum value for the sequence

max - Maximum value for the sequence

start - Start value for the sequence

increment - Increment value for the sequence

cache_size - Cache size for the sequence

Returns:

The statement for getting the next id from the sequence

getSequenceNextStmt

public java.lang.String getSequenceNextStmt(java.lang.String sequence_name)

Accessor for the statement for getting the next id from the sequence for this datastore.

Specified by:

getSequenceNextStmt in interface RDBMSAdapter

Overrides:

getSequenceNextStmt in class DatabaseAdapter

Parameters:

sequence_name - Name of the sequence

Returns:

The statement for getting the next id for the sequence

toStringExpression

public org.datanucleus.store.mapped.expression.StringExpression toStringExpression(org.datanucleus.store.mapped.expression.StringLiteral expr)

A String conversion that converts a String literal to String expression. It will allow the String to only be evaluated at runtime. In SQL, it should compile something like:

 CAST(999999 AS VARCHAR(32672))
 

Specified by:

toStringExpression in interface org.datanucleus.store.mapped.expression.ExpressionConversionAdapter

Overrides:

toStringExpression in class DatabaseAdapter

Parameters:

expr - The NumericExpression

Returns:

the StringExpression

translateMethod

public org.datanucleus.store.mapped.expression.StringExpression translateMethod(org.datanucleus.store.mapped.expression.ScalarExpression expr,
                                                                                org.datanucleus.store.mapped.expression.ScalarExpression toExpr,
                                                                                org.datanucleus.store.mapped.expression.ScalarExpression fromExpr)

Method to translate all chars in this expression to the fromExpr which corresponds to toExpr.

Specified by:

translateMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

translateMethod in class DatabaseAdapter

Returns:

The expression.

startsWithMethod

public org.datanucleus.store.mapped.expression.BooleanExpression startsWithMethod(org.datanucleus.store.mapped.expression.ScalarExpression source,
                                                                                  org.datanucleus.store.mapped.expression.ScalarExpression str)

Method to handle the starts with operation.

Specified by:

startsWithMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

startsWithMethod in class DatabaseAdapter

Parameters:

source - The expression with the searched string

str - The expression for the search string

Returns:

The expression.

concatOperator

public org.datanucleus.store.mapped.expression.ScalarExpression concatOperator(org.datanucleus.store.mapped.expression.ScalarExpression operand1,
                                                                               org.datanucleus.store.mapped.expression.ScalarExpression operand2)

If only one operand expression is of type String, then string conversion is performed on the other operand to produce a string at run time. The result is a reference to a String object (newly created, unless the expression is a compile-time constant expression (§15.28))that is the concatenation of the two operand strings. The characters of the left-hand operand precede the characters of the right-hand operand in the newly created string. If an operand of type String is null, then the string "null" is used instead of that operand. "null" is used instead of that operand.

Concatenates two or more character or binary strings, columns, or a combination of strings and column names into one expression (a string operator).

Specified by:

concatOperator in interface org.datanucleus.store.mapped.expression.ExpressionOperatorAdapter

Overrides:

concatOperator in class DatabaseAdapter

Parameters:

operand1 - the left expression

operand2 - the right expression

Returns:

The Expression for concatenation

endsWithMethod

public org.datanucleus.store.mapped.expression.BooleanExpression endsWithMethod(org.datanucleus.store.mapped.expression.ScalarExpression leftOperand,
                                                                                org.datanucleus.store.mapped.expression.ScalarExpression rightOperand)

Returns whether this string ends with the specified string.

Specified by:

endsWithMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

endsWithMethod in class DatabaseAdapter

Parameters:

leftOperand - the source string

rightOperand - The string to compare against.

Returns:

Whether it ends with the string.

newTableExpression

public org.datanucleus.store.mapped.expression.LogicSetExpression newTableExpression(org.datanucleus.store.mapped.expression.QueryExpression qs,
                                                                                     org.datanucleus.store.mapped.DatastoreContainerObject table,
                                                                                     org.datanucleus.store.mapped.DatastoreIdentifier rangeVar)

Description copied from class: DatabaseAdapter

Returns a new TableExpression object appropriate for this DBMS. This should be an instance of one of the three built-in styles of table expression:

• TableExprAsJoins
• TableExprAsSubjoins
• TableExprAsSubquery

TableExprAsSubjoins is the default, which arguably produces the most readable SQL but doesn't work on all DBMS's. TableExprAsSubjoins should work anywhere, but may be less efficient.

Specified by:

newTableExpression in interface RDBMSAdapter

Overrides:

newTableExpression in class DatabaseAdapter

Parameters:

qs - The query statement in which the table expression will be included.

table - The main table in the expression.

rangeVar - The SQL alias, or "range variable", to assign to the expression or to the main table.

Returns:

The expression

modOperator

public org.datanucleus.store.mapped.expression.NumericExpression modOperator(org.datanucleus.store.mapped.expression.ScalarExpression operand1,
                                                                             org.datanucleus.store.mapped.expression.ScalarExpression operand2)

Method to generate a modulus expression. The binary % operator is said to yield the remainder of its operands from an implied division; the left-hand operand is the dividend and the right-hand operand is the divisor. This returns MOD(expr1, expr2).

Specified by:

modOperator in interface org.datanucleus.store.mapped.DatastoreAdapter

Specified by:

modOperator in interface org.datanucleus.store.mapped.expression.ExpressionOperatorAdapter

Overrides:

modOperator in class DatabaseAdapter

Parameters:

operand1 - the left expression

operand2 - the right expression

Returns:

The Expression for modulus

getNumericExpressionForMethod

public org.datanucleus.store.mapped.expression.NumericExpression getNumericExpressionForMethod(java.lang.String method,
                                                                                               org.datanucleus.store.mapped.expression.ScalarExpression expr)

Accessor for a numeric expression to represent the method call, with passed argument.

Specified by:

getNumericExpressionForMethod in interface org.datanucleus.store.mapped.DatastoreAdapter

Overrides:

getNumericExpressionForMethod in class DatabaseAdapter

Parameters:

method - The method (case insensitive)

expr - The argument to the method

Returns:

The numeric expression that results

substringMethod

public org.datanucleus.store.mapped.expression.StringExpression substringMethod(org.datanucleus.store.mapped.expression.StringExpression str,
                                                                                org.datanucleus.store.mapped.expression.NumericExpression begin)

Description copied from class: DatabaseAdapter

Returns the appropriate SQL expression for the JDOQL String.substring(str,begin) method. It should return something like:

 SUBSTRING(str FROM begin)
 

Note that the value of begin is base 0(Java-style), while most SQL string functions use base 1.

Specified by:

substringMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

substringMethod in class DatabaseAdapter

Parameters:

str - The first argument to the substring() method.

begin - The second argument to the substring() method.

Returns:

The text of the SQL expression.

substringMethod

public org.datanucleus.store.mapped.expression.StringExpression substringMethod(org.datanucleus.store.mapped.expression.StringExpression str,
                                                                                org.datanucleus.store.mapped.expression.NumericExpression begin,
                                                                                org.datanucleus.store.mapped.expression.NumericExpression end)

Description copied from class: DatabaseAdapter

Returns the appropriate SQL expression for the JDOQL String.substring(str,begin,end) method. It should return something like:

 SUBSTRING(str FROM begin FOR len)
 

Note that the value of begin is base 0 (Java-style), while most SQL string functions use base 1. Note also that an end position is given, while most SQL substring functions take a length.

Specified by:

substringMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

substringMethod in class DatabaseAdapter

Parameters:

str - The first argument to the substring() method.

begin - The second argument to the substring() method.

end - The third argument to the substring() method.

Returns:

The text of the SQL expression.

trimMethod

public org.datanucleus.store.mapped.expression.StringExpression trimMethod(org.datanucleus.store.mapped.expression.StringExpression str,
                                                                           boolean leading,
                                                                           boolean trailing)

Returns the appropriate SQL expression for the java query "trim" method. It should return something like:

LTRIM(RTRIM(str))

Specified by:

trimMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

trimMethod in class DatabaseAdapter

Parameters:

str - The first argument to the trim() method.

leading - Whether to trim leading spaces

trailing - Whether to trim trailing spaces

Returns:

The text of the SQL expression.

indexOfMethod

public org.datanucleus.store.mapped.expression.NumericExpression indexOfMethod(org.datanucleus.store.mapped.expression.ScalarExpression source,
                                                                               org.datanucleus.store.mapped.expression.ScalarExpression str,
                                                                               org.datanucleus.store.mapped.expression.NumericExpression from)

Returns the appropriate SQL expression for the JDOQL String.indexOf() method. It should return something like:

 LOCATE(str, substr [,pos])-1
 

since LOCATE returns the first character as position 1. Similarly the "pos" is based on the first position being 1.

Specified by:

indexOfMethod in interface org.datanucleus.store.mapped.expression.ExpressionMethodAdapter

Overrides:

indexOfMethod in class DatabaseAdapter

Parameters:

source - The expression we want to search.

str - The argument to the indexOf() method.

from - The from position

Returns:

The text of the SQL expression.