ParameterExpression
Overview
This class is an implementation of ParameterExpression and is used to represent parameters in Dynamic Where expressions.
This is one of the classes used to dynamically build WHERE statements from code.
For example, a WHERE clause of this query
SELECT * FROM Orders WHERE Customer = :CustomerID
represented using ParameterExpression would look like this:
WhereExpression lResult;
lResult = new BinaryExpression(
new FieldExpression("Customer"),
new ParameterExpression("CustomerID", DataType.Integer, 0),
BinaryOperator.Equal);
Location
- Reference: com.remobjects.dataabstract.jar
- Package: com.remobjects.dataabstract.expressions
- Ancestry: Object | WhereExpression | ParameterExpression
constructor
Creates a new instance of the ParameterExpression class.
constructor
ParameterExpression()
constructor (String, DataType, Integer)
Creates a new instance of the ParameterExpression class with a specified name, type and size of the parameter.
constructor(aName: String; aType: DataType; aSize: Integer)
ParameterExpression(String aName, DataType aType, Integer aSize)
Parameters:
- aName: The name of the parameter.
- aType: The data type of the parameter.
- aSize: The size of the parameter; used if applicable to the type.
combine (WhereExpression, WhereExpression): WhereExpression (declared in WhereExpression)
Creates a new BinaryExpression from the given aLeft and aRight operands using BinaryOperator.
class method combine(aLeft: WhereExpression; aRight: WhereExpression): WhereExpression
static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight)
Parameters:
- aLeft: The left operand to be combined.
- aRight: The right operand to be combined.
combine (WhereExpression, WhereExpression, BinaryOperator): WhereExpression (declared in WhereExpression)
Creates a new BinaryExpression from the given aLeft and aRight operands using the given operator.
class method combine(aLeft: WhereExpression; aRight: WhereExpression; anOperator: BinaryOperator): WhereExpression
static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight, BinaryOperator anOperator)
Parameters:
- aLeft: The left operand to be combined.
- aRight: The right operand to be combined.
- anOperator: The operator to be used in combining.
fromString (declared in WhereExpression)
Creates a new WhereExpression from the specified string, which should contain XML node in the correct Dynamic Where XML Format.
class method fromString(anXml: String): WhereExpression
static WhereExpression fromString(String anXml)
Parameters:
- anXml: The given XML string.
fromStringToSql (declared in WhereExpression)
A helper method to convert a XML string into SQL string.
class method fromStringToSql(anXml: String): String
static String fromStringToSql(String anXml)
Parameters:
- anXml: The XML string to be converted.
fromXmlNode (declared in WhereExpression)
Creates a new WhereExpression from the given XML node, which should be in the correct Dynamic Where XML Format.
class method fromXmlNode(aNode: Node): WhereExpression
static WhereExpression fromXmlNode(Node aNode)
Parameters:
- aNode: The XML node to be parsed.
Kind
Represents the type of WHERE expression.
property Kind: WhereKind read;
WhereKind Kind { __get; }
ParameterName
Name of the parameter represented by this instance.
property ParameterName: String read write;
String ParameterName { __get; __set; }
parseExpression (declared in WhereExpression)
Creates new Where expression from XML node.
class method parseExpression(node: Node): WhereExpression
static WhereExpression parseExpression(Node node)
Parameters:
- node: XML node
readFromXml
Initializes the current expression from the given XML node.
method readFromXml(aNode: Node)
void readFromXml(Node aNode)
Parameters:
- aNode: The XML node to be parsed.
Size
Size of the parameter.
property Size: Integer read write;
Integer Size { __get; __set; }
toSqlString (declared in WhereExpression)
Creates an SQL representation of the current where expression instance
method toSqlString: String
String toSqlString()
toSqlString (StringBuilder)
Creates an SQL representation of the current where expression instance and appends it to the provided StringBuilder.
method toSqlString(aDestination: StringBuilder)
void toSqlString(StringBuilder aDestination)
Parameters:
- aDestination: The destination string builder to be appended.
toString (declared in WhereExpression)
Returns a SQL string representation of the current expression.
method toString: String
String toString()
toXmlNode (declared in WhereExpression)
Creates a query node (in the Dynamic Where XML Format) from the current expression.
method toXmlNode: Node
Node toXmlNode()
toXmlString (declared in WhereExpression)
Creates the query node (in the Dynamic Where XML Format) from current expression and returns it in the string format.
method toXmlString: String
String toXmlString()
Type
Specifies the type of the parameter. Type can be any from the DataType enum.
property Type: DataType read write;
DataType Type { __get; __set; }
validate (declared in WhereExpression)
Validates the current expression with the WhereValidator and returns TRUE if it contains no errors. The main purpose of the validation is to scan all objects of WhereExpession tree and make sure that they contain correct field names.
method validate: Boolean
Boolean validate()
validate (WhereExpression): Boolean (declared in WhereExpression)
Validates the provided WhereExpression with the WhereValidator and returns TRUE if it contains no errors. The main purpose of the validation is to scan all objects of WhereExpession tree and make sure that it contains correct field names.
class method validate(anExpression: WhereExpression): Boolean
static Boolean validate(WhereExpression anExpression)
Parameters:
- anExpression: The expression to be validated.
writeToXml
Creates where node (in the Dynamic Where XML Format) from expression.
method writeToXml(aNode: Node)
void writeToXml(Node aNode)
Parameters:
- aNode: The given parent XML node.
Kind
Represents the type of WHERE expression.
property Kind: WhereKind read;
WhereKind Kind { __get; }
ParameterName
Name of the parameter represented by this instance.
property ParameterName: String read write;
String ParameterName { __get; __set; }
Size
Size of the parameter.
property Size: Integer read write;
Integer Size { __get; __set; }
Type
Specifies the type of the parameter. Type can be any from the DataType enum.
property Type: DataType read write;
DataType Type { __get; __set; }
combine (WhereExpression, WhereExpression): WhereExpression (declared in WhereExpression)
Creates a new BinaryExpression from the given aLeft and aRight operands using BinaryOperator.
class method combine(aLeft: WhereExpression; aRight: WhereExpression): WhereExpression
static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight)
Parameters:
- aLeft: The left operand to be combined.
- aRight: The right operand to be combined.
combine (WhereExpression, WhereExpression, BinaryOperator): WhereExpression (declared in WhereExpression)
Creates a new BinaryExpression from the given aLeft and aRight operands using the given operator.
class method combine(aLeft: WhereExpression; aRight: WhereExpression; anOperator: BinaryOperator): WhereExpression
static WhereExpression combine(WhereExpression aLeft, WhereExpression aRight, BinaryOperator anOperator)
Parameters:
- aLeft: The left operand to be combined.
- aRight: The right operand to be combined.
- anOperator: The operator to be used in combining.
fromString (declared in WhereExpression)
Creates a new WhereExpression from the specified string, which should contain XML node in the correct Dynamic Where XML Format.
class method fromString(anXml: String): WhereExpression
static WhereExpression fromString(String anXml)
Parameters:
- anXml: The given XML string.
fromStringToSql (declared in WhereExpression)
A helper method to convert a XML string into SQL string.
class method fromStringToSql(anXml: String): String
static String fromStringToSql(String anXml)
Parameters:
- anXml: The XML string to be converted.
fromXmlNode (declared in WhereExpression)
Creates a new WhereExpression from the given XML node, which should be in the correct Dynamic Where XML Format.
class method fromXmlNode(aNode: Node): WhereExpression
static WhereExpression fromXmlNode(Node aNode)
Parameters:
- aNode: The XML node to be parsed.
parseExpression (declared in WhereExpression)
Creates new Where expression from XML node.
class method parseExpression(node: Node): WhereExpression
static WhereExpression parseExpression(Node node)
Parameters:
- node: XML node
validate (WhereExpression): Boolean (declared in WhereExpression)
Validates the provided WhereExpression with the WhereValidator and returns TRUE if it contains no errors. The main purpose of the validation is to scan all objects of WhereExpession tree and make sure that it contains correct field names.
class method validate(anExpression: WhereExpression): Boolean
static Boolean validate(WhereExpression anExpression)
Parameters:
- anExpression: The expression to be validated.
constructor
Creates a new instance of the ParameterExpression class.
constructor
ParameterExpression()
constructor (String, DataType, Integer)
Creates a new instance of the ParameterExpression class with a specified name, type and size of the parameter.
constructor(aName: String; aType: DataType; aSize: Integer)
ParameterExpression(String aName, DataType aType, Integer aSize)
Parameters:
- aName: The name of the parameter.
- aType: The data type of the parameter.
- aSize: The size of the parameter; used if applicable to the type.
readFromXml
Initializes the current expression from the given XML node.
method readFromXml(aNode: Node)
void readFromXml(Node aNode)
Parameters:
- aNode: The XML node to be parsed.
toSqlString (declared in WhereExpression)
Creates an SQL representation of the current where expression instance
method toSqlString: String
String toSqlString()
toSqlString (StringBuilder)
Creates an SQL representation of the current where expression instance and appends it to the provided StringBuilder.
method toSqlString(aDestination: StringBuilder)
void toSqlString(StringBuilder aDestination)
Parameters:
- aDestination: The destination string builder to be appended.
toString (declared in WhereExpression)
Returns a SQL string representation of the current expression.
method toString: String
String toString()
toXmlNode (declared in WhereExpression)
Creates a query node (in the Dynamic Where XML Format) from the current expression.
method toXmlNode: Node
Node toXmlNode()
toXmlString (declared in WhereExpression)
Creates the query node (in the Dynamic Where XML Format) from current expression and returns it in the string format.
method toXmlString: String
String toXmlString()
validate (declared in WhereExpression)
Validates the current expression with the WhereValidator and returns TRUE if it contains no errors. The main purpose of the validation is to scan all objects of WhereExpession tree and make sure that they contain correct field names.
method validate: Boolean
Boolean validate()
writeToXml
Creates where node (in the Dynamic Where XML Format) from expression.
method writeToXml(aNode: Node)
void writeToXml(Node aNode)
Parameters:
- aNode: The given parent XML node.