Module org.apache.derby.engine

Package org.apache.derby.vti

Class Restriction.ColumnQualifier

java.lang.Object

org.apache.derby.vti.Restriction

org.apache.derby.vti.Restriction.ColumnQualifier

All Implemented Interfaces:

Serializable

Enclosing class:

Restriction

public static class Restriction.ColumnQualifier
extends Restriction

A simple comparison of a column to a constant value. The comparison has the form:

 column OP constant
 

where OP is one of the following:

  <     =     <=     >      >=    IS NULL    IS NOT NULL
 

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.derby.vti.Restriction

Restriction.AND, Restriction.ColumnQualifier, Restriction.OR

Field Summary

Fields

Modifier and Type	Field	Description
static final int	ORDER_OP_EQUALS	Ordering operation constant representing '='
static final int	ORDER_OP_GREATEROREQUALS	Ordering operation constant representing '>='
static final int	ORDER_OP_GREATERTHAN	Ordering operation constant representing '>'
static final int	ORDER_OP_ISNOTNULL	Ordering operation constant representing 'IS NOT NULL'
static final int	ORDER_OP_ISNULL	Ordering operation constant representing 'IS NULL'
static final int	ORDER_OP_LESSOREQUALS	Ordering operation constant representing '<='
static final int	ORDER_OP_LESSTHAN	Ordering operation constant representing '<'
static final int	ORDER_OP_NOT_EQUALS	Ordering operation constant representing '!
static final long	serialVersionUID	Derby serializes these objects in PreparedStatements

Constructor Summary

Constructors

Constructor	Description
ColumnQualifier(String columnName, int comparisonOperator, Object constantOperand)	Construct from pieces.

Method Summary

Modifier and Type	Method	Description
String	getColumnName()	The name of the column being compared.
int	getComparisonOperator()	The type of comparison to perform.
Object	getConstantOperand()	Get the constant value to which the column should be compared.
String	toSQL()	Turn this Restriction into WHERE clause text.

Methods inherited from class java.lang.Object

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

Field Details

serialVersionUID

public static final long serialVersionUID

Derby serializes these objects in PreparedStatements

See Also:

• Constant Field Values

ORDER_OP_LESSTHAN

public static final int ORDER_OP_LESSTHAN

Ordering operation constant representing '<'

See Also:

• Constant Field Values

ORDER_OP_EQUALS

public static final int ORDER_OP_EQUALS

Ordering operation constant representing '='

See Also:

• Constant Field Values

ORDER_OP_LESSOREQUALS

public static final int ORDER_OP_LESSOREQUALS

Ordering operation constant representing '<='

See Also:

• Constant Field Values

ORDER_OP_GREATERTHAN

public static final int ORDER_OP_GREATERTHAN

Ordering operation constant representing '>'

See Also:

• Constant Field Values

ORDER_OP_GREATEROREQUALS

public static final int ORDER_OP_GREATEROREQUALS

Ordering operation constant representing '>='

See Also:

• Constant Field Values

ORDER_OP_ISNULL

public static final int ORDER_OP_ISNULL

Ordering operation constant representing 'IS NULL'

See Also:

• Constant Field Values

ORDER_OP_ISNOTNULL

public static final int ORDER_OP_ISNOTNULL

Ordering operation constant representing 'IS NOT NULL'

See Also:

• Constant Field Values

ORDER_OP_NOT_EQUALS

public static final int ORDER_OP_NOT_EQUALS

Ordering operation constant representing '!='

See Also:

• Constant Field Values

Constructor Details

ColumnQualifier

public ColumnQualifier(String columnName,
 int comparisonOperator,
 Object constantOperand)

Construct from pieces.

Parameters:

columnName - Name of column as declared in the CREATE FUNCTION statement.

comparisonOperator - One of the ORDER_OP constants.

constantOperand - Constant value to which the column should be compared.

Method Details

getColumnName

public String getColumnName()

The name of the column being compared.

Returns:

the name of the column being compared

getComparisonOperator

public int getComparisonOperator()

The type of comparison to perform. This is one of the ORDER_OP constants defined above.

Returns:

an ORDER_OP representing the type of comparison to perform

getConstantOperand

public Object getConstantOperand()

Get the constant value to which the column should be compared. The constant value must be an Object of the Java type which corresponds to the SQL type of the column. The column's SQL type was declared in the CREATE FUNCTION statement. The mapping of SQL types to Java types is defined in table 4 of chapter 14 of the original JDBC 1 specification (dated 1996). Bascially, these are the Java wrapper values you would expect. For instance, SQL INT maps to java.lang.Integer, SQL CHAR maps to java.lang.String, etc.. This object will be null if the comparison operator is ORDER_OP_ISNULL or ORDER_OP_ISNOTNULL.

Returns:

the constant with which the column is being compared

toSQL

public String toSQL()

Turn this Restriction into WHERE clause text.

Specified by:

toSQL in class Restriction

Returns:

this Restriction as WHERE clause text