com.caucho.db.sql

Class Expr

java.lang.Object

com.caucho.db.sql.Expr

Direct Known Subclasses:

ExistsEvalExpr, FunExpr, GroupResultExpr, SubSelectEvalExpr, SubSelectExpr, SubSelectParamExpr

@Module
public abstract class Expr
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
static int	FALSE
protected static L10N	L
static int	TRUE
static int	UNKNOWN

Constructor Summary

Constructors

Constructor and Description
Expr()

Method Summary

Modifier and Type	Method and Description
Expr	bind(Query query)
long	cost(java.util.ArrayList<FromItem> fromList) Returns the cost based on the given FromList.
com.caucho.db.sql.Order	createOrder(int index) Returns the order.
int	evalBoolean(QueryContext context) Evaluates the expression as a boolean.
byte[]	evalBytes(QueryContext context) Evaluates the expression as a stream.
long	evalDate(QueryContext context) Evaluates the expression as a date.
double	evalDouble(QueryContext context) Evaluates the expression as a double.
boolean	evalEqual(QueryContext context, byte[] data)
boolean	evalEqual(QueryContext context, java.lang.String evalString)
void	evalGroup(QueryContext context) Evaluates aggregate functions during the group phase.
long	evalLong(QueryContext context) Evaluates the expression as a long.
java.io.InputStream	evalStream(QueryContext context) Evaluates the expression as a stream.
java.lang.String	evalString(QueryContext context) Evaluates the expression as a string.
int	evalToBuffer(QueryContext context, byte[] buffer, int offset) Evaluates the expression to a buffer
int	evalToBuffer(QueryContext context, byte[] buffer, int off, Column.ColumnType columnType) Evaluates the expression to a buffer
void	evalToResult(QueryContext context, SelectResult result) Evaluates the expression, writing to the result stream.
com.caucho.db.sql.RowIterateExpr	getIndexExpr(FromItem fromItem) Returns an index expression if available.
java.lang.String	getName() Returns any column name.
int	getSQLType()
Table	getTable() Returns the table.
java.lang.Class<?>	getType() Returns the expected result type of the expression.
Column.ColumnType	getTypeCode() Returns the java type code if known.
long	indexCost(java.util.ArrayList<FromItem> costItems) Returns the cost bonus for an index.
long	indexSubCost(java.util.ArrayList<FromItem> costItems) Returns the cost bonus for an index.
void	initGroup(QueryContext context) Initializes aggregate functions during the group phase.
boolean	isBinaryStream(QueryContext context) Returns true if the expression returns a binary stream.
boolean	isBoolean() Returns true if the expression returns a boolean.
boolean	isDouble() Returns true if the expression returns a double.
boolean	isLong() Returns true if the expression returns a long.
boolean	isNull(QueryContext context) Returns true if result is null
boolean	isNullable() Returns true if the expression can return a null value.
boolean	isParam() Returns true for a parameter expression.
boolean	isSelect(QueryContext context) Returns true if the expression selects the row.
void	splitAnd(java.util.ArrayList<Expr> andProduct) Splits the expr into and blocks.
long	subCost(java.util.ArrayList<FromItem> fromList) Returns the cost based on the given FromList.
void	updateDouble(QueryContext context, double value) Updates the expression as a double
void	updateLong(QueryContext context, long value) Updates the expression as a long
void	updateString(QueryContext context, java.lang.String value) Updates the expression as a string

Methods inherited from class java.lang.Object

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

Field Detail

L

protected static final L10N L

UNKNOWN

public static final int UNKNOWN

See Also:

Constant Field Values

FALSE

public static final int FALSE

See Also:

Constant Field Values

TRUE

public static final int TRUE

See Also:

Constant Field Values

Constructor Detail

Expr

public Expr()

Method Detail

bind

public Expr bind(Query query)
          throws java.sql.SQLException

Throws:

java.sql.SQLException

getType

public java.lang.Class<?> getType()

Returns the expected result type of the expression.

getTypeCode

public Column.ColumnType getTypeCode()

Returns the java type code if known.

getSQLType

public int getSQLType()

isLong

public boolean isLong()

Returns true if the expression returns a long.

isDouble

public boolean isDouble()

Returns true if the expression returns a double.

isBoolean

public boolean isBoolean()

Returns true if the expression returns a boolean.

isBinaryStream

public boolean isBinaryStream(QueryContext context)

Returns true if the expression returns a binary stream.

isParam

public boolean isParam()

Returns true for a parameter expression.

isNullable

public boolean isNullable()

Returns true if the expression can return a null value.

getName

public java.lang.String getName()

Returns any column name.

getTable

public Table getTable()

Returns the table.

splitAnd

public void splitAnd(java.util.ArrayList<Expr> andProduct)

Splits the expr into and blocks.

cost

public long cost(java.util.ArrayList<FromItem> fromList)

Returns the cost based on the given FromList.

subCost

public long subCost(java.util.ArrayList<FromItem> fromList)

Returns the cost based on the given FromList.

indexCost

public long indexCost(java.util.ArrayList<FromItem> costItems)

Returns the cost bonus for an index.

indexSubCost

public long indexSubCost(java.util.ArrayList<FromItem> costItems)

Returns the cost bonus for an index.

getIndexExpr

public com.caucho.db.sql.RowIterateExpr getIndexExpr(FromItem fromItem)

Returns an index expression if available.

createOrder

public com.caucho.db.sql.Order createOrder(int index)

Returns the order.

isNull

public boolean isNull(QueryContext context)
               throws java.sql.SQLException

Returns true if result is null

Parameters:

rows - the current database tuple

Returns:

true if null

Throws:

java.sql.SQLException

isSelect

public boolean isSelect(QueryContext context)
                 throws java.sql.SQLException

Returns true if the expression selects the row.

Parameters:

rows - the current database tuple

Returns:

the boolean value

Throws:

java.sql.SQLException

evalBoolean

public int evalBoolean(QueryContext context)
                throws java.sql.SQLException

Evaluates the expression as a boolean.

Parameters:

rows - the current database tuple

Returns:

the boolean value

Throws:

java.sql.SQLException

evalString

public java.lang.String evalString(QueryContext context)
                            throws java.sql.SQLException

Evaluates the expression as a string.

Parameters:

rows - the current database tuple

Returns:

the string value

Throws:

java.sql.SQLException

updateString

public void updateString(QueryContext context,
                         java.lang.String value)
                  throws java.sql.SQLException

Updates the expression as a string

Throws:

java.sql.SQLException

evalLong

public long evalLong(QueryContext context)
              throws java.sql.SQLException

Evaluates the expression as a long.

Parameters:

rows - the current database tuple

Returns:

the long value

Throws:

java.sql.SQLException

updateLong

public void updateLong(QueryContext context,
                       long value)
                throws java.sql.SQLException

Updates the expression as a long

Throws:

java.sql.SQLException

evalDouble

public double evalDouble(QueryContext context)
                  throws java.sql.SQLException

Evaluates the expression as a double.

Parameters:

rows - the current database tuple

Returns:

the double value

Throws:

java.sql.SQLException

updateDouble

public void updateDouble(QueryContext context,
                         double value)
                  throws java.sql.SQLException

Updates the expression as a double

Throws:

java.sql.SQLException

evalDate

public long evalDate(QueryContext context)
              throws java.sql.SQLException

Evaluates the expression as a date.

Parameters:

rows - the current database tuple

Returns:

the double value

Throws:

java.sql.SQLException

evalToResult

public void evalToResult(QueryContext context,
                         SelectResult result)
                  throws java.sql.SQLException

Evaluates the expression, writing to the result stream.

Parameters:

result - the output result

Throws:

java.sql.SQLException

evalStream

public java.io.InputStream evalStream(QueryContext context)
                               throws java.sql.SQLException

Evaluates the expression as a stream.

Parameters:

rows - the current database tuple

Returns:

the string value

Throws:

java.sql.SQLException

evalBytes

public byte[] evalBytes(QueryContext context)
                 throws java.sql.SQLException

Evaluates the expression as a stream.

Parameters:

rows - the current database tuple

Returns:

the string value

Throws:

java.sql.SQLException

evalToBuffer

public int evalToBuffer(QueryContext context,
                        byte[] buffer,
                        int offset)
                 throws java.sql.SQLException

Evaluates the expression to a buffer

Parameters:

result - the result buffer

Returns:

the length of the result

Throws:

java.sql.SQLException

evalToBuffer

public int evalToBuffer(QueryContext context,
                        byte[] buffer,
                        int off,
                        Column.ColumnType columnType)
                 throws java.sql.SQLException

Evaluates the expression to a buffer

Parameters:

result - the result buffer

Returns:

the length of the result

Throws:

java.sql.SQLException

initGroup

public void initGroup(QueryContext context)
               throws java.sql.SQLException

Initializes aggregate functions during the group phase.

Parameters:

context - the current database tuple

Throws:

java.sql.SQLException

evalGroup

public void evalGroup(QueryContext context)
               throws java.sql.SQLException

Evaluates aggregate functions during the group phase.

Parameters:

context - the current database tuple

Throws:

java.sql.SQLException

evalEqual

public boolean evalEqual(QueryContext context,
                         java.lang.String evalString)
                  throws java.sql.SQLException

Throws:

java.sql.SQLException

evalEqual

public boolean evalEqual(QueryContext context,
                         byte[] data)
                  throws java.sql.SQLException

Throws:

java.sql.SQLException