wt.query
Interface Expression

All Known Subinterfaces:

ColumnExpression, OrderByExpression, RelationalExpression

All Known Implementing Classes:

ArrayExpression, ArrayTableExpression, ClassAttribute, ColumnListExpression, ConstantExpression, FixedLengthStringExpression, KeywordExpression, RangeExpression, SQLFunction, SubSelectExpression, TableColumn

public interface Expression

This interface defines an expression that can be used in a SQL statement.

Supported API: true

Extendable: false

Field Summary

static String

FROM_COUNT Label for the attribute; Number of from index values that this expression requires Supported API: false

Method Summary

int	getFromCount() Gets the value of the attribute: FROM_COUNT.
int	setFromAlias(String[] a_aliases, int a_offset) This method sets the FROM clause alias for this expression.
int	validate(TableExpression[] a_tableExpressions, int a_offset) This method validates this expression against the specified table expression.

Field Detail

FROM_COUNT

public static final String FROM_COUNT

Label for the attribute; Number of from index values that this expression requires

Supported API: false

See Also:

Constant Field Values

Method Detail

getFromCount

public int getFromCount()

Gets the value of the attribute: FROM_COUNT. Number of from index values that this expression requires

Supported API: false

Returns:

int

validate

public int validate(TableExpression[] a_tableExpressions,
                    int a_offset)
             throws QueryException

This method validates this expression against the specified table expression. A QueryException is thrown if this expression is not valid.

Supported API: false

Parameters:

a_tableExpressions - Table expression to validate against.

a_offset - Offset index into the TableExpression array for the next valid TableExpression

Returns:

number of TableExpressions validated

Throws:

QueryException

setFromAlias

public int setFromAlias(String[] a_aliases,
                        int a_offset)

This method sets the FROM clause alias for this expression. This alias is used in this Expression in place of the corresponding TableExpression.

Supported API: false

Parameters:

a_aliases - Array of aliases for expressions

a_offset - Offset index into the alias array for the next valid alias

Returns:

number of aliases used