org.vanilladb.core.query.parse

Class ModifyData

java.lang.Object

org.vanilladb.core.query.parse.ModifyData

public class ModifyData
extends Object

Data for the SQL update statement.

Constructor Summary

Constructors

Constructor and Description
ModifyData(String tblName, Map<String,Expression> fldVals, Predicate pred) Saves the table name, the modified field and its new value, and the predicate.

Method Summary

Modifier and Type	Method and Description
Expression	newValue(String fldName) Returns an expression.
Predicate	pred() Returns the predicate that describes which records should be modified.
String	tableName() Returns the name of the affected table.
Collection<String>	targetFields() Returns the fields whose values will be modified

Methods inherited from class java.lang.Object

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

Constructor Detail

ModifyData

public ModifyData(String tblName,
                  Map<String,Expression> fldVals,
                  Predicate pred)

Saves the table name, the modified field and its new value, and the predicate.

Parameters:

tblName - the name of the affected table

fldVals - the list of names of the target fields

pred - the modification predicate

Method Detail

tableName

public String tableName()

Returns the name of the affected table.

Returns:

the name of the affected table

targetFields

public Collection<String> targetFields()

Returns the fields whose values will be modified

Returns:

the list of names of the target fields

newValue

public Expression newValue(String fldName)

Returns an expression. Evaluating this expression for a record produces the value that will be stored in the record's target field.

Parameters:

fldName - the name of the modified field

Returns:

the target expression

pred

public Predicate pred()

Returns the predicate that describes which records should be modified.

Returns:

the modification predicate