Comparison

Example comparison expressions are ID=1, NAME=NAME, NAME IS NULL.

Methods
static boolean	compareNotNull(Database database, Value l, Value r, int compareType) Compare two values, given the values are not NULL.
static boolean	compareNotNull(Database database, Value l, Value r, int compareType) Compare two values, given the values are not NULL. Parameters: database - the database l - the first value r - the second value compareType - the compare type Returns: true if the comparison indicated by the comparison type evaluates to true
static String	getCompareOperator(int compareType) Get the comparison operator string ("=", ">",...).
static String	getCompareOperator(int compareType) Get the comparison operator string ("=", ">",...). Parameters: compareType - the compare type Returns: the string
void	addFilterConditions(TableFilter filter, boolean outerJoin)
void	addFilterConditions(TableFilter filter, boolean outerJoin)
void	createIndexConditions(Session session, TableFilter filter)
void	createIndexConditions(Session session, TableFilter filter)
Expression	getAdditional(Session session, Comparison other, boolean and) Get an additional condition if possible.
Expression	getAdditional(Session session, Comparison other, boolean and) Get an additional condition if possible. Example: given two conditions A=B AND B=C, the new condition A=C is returned. Given the two conditions A=1 OR A=2, the new condition A IN(1, 2) is returned. Parameters: session - the session other - the second condition and - true for AND, false for OR Returns: null or the third condition
int	getCost()
int	getCost()
Expression	getExpression(boolean getLeft) Get the left or the right sub-expression of this condition.
Expression	getExpression(boolean getLeft) Get the left or the right sub-expression of this condition. Parameters: getLeft - true to get the left sub-expression, false to get the right sub-expression. Returns: the sub-expression
Expression	getIfEquals(Expression match) Get the other expression if this is an equals comparison and the other expression matches.
Expression	getIfEquals(Expression match) Get the other expression if this is an equals comparison and the other expression matches. Parameters: match - the expression that should match Returns: null if no match, the other expression if there is a match
Expression	getNotIfPossible(Session session)
Expression	getNotIfPossible(Session session)
String	getSQL()
String	getSQL()
Value	getValue(Session session)
Value	getValue(Session session)
boolean	isEverything(ExpressionVisitor visitor)
boolean	isEverything(ExpressionVisitor visitor)
void	mapColumns(ColumnResolver resolver, int level)
void	mapColumns(ColumnResolver resolver, int level)
Expression	optimize(Session session)
Expression	optimize(Session session)
void	setEvaluatable(TableFilter tableFilter, boolean b)
void	setEvaluatable(TableFilter tableFilter, boolean b)
void	updateAggregate(Session session)
void	updateAggregate(Session session)

Fields
static int	BIGGER = 2
static int	BIGGER_EQUAL = 1
static int	EQUAL = 0
static int	EQUAL_NULL_SAFE = 16
static int	FALSE = 8
static int	IN_LIST = 9
static int	IN_QUERY = 10
static int	IS_NOT_NULL = 7
static int	IS_NULL = 6
static int	NOT_EQUAL = 5
static int	NOT_EQUAL_NULL_SAFE = 21
static int	NULL_SAFE = 16
static int	SMALLER = 4
static int	SMALLER_EQUAL = 3
static int	SPATIAL_INTERSECTS = 11

EQUAL = 0

The comparison type meaning = as in ID=1.

BIGGER_EQUAL = 1

The comparison type meaning >= as in ID>=1.

IN_QUERY = 10

This is a pseudo comparison type that is only used for index conditions. It means equals any value of a list. Example: IN(SELECT ...).

SPATIAL_INTERSECTS = 11

This is a comparison type that is only used for spatial index conditions (operator "&&").

EQUAL_NULL_SAFE = 16

The comparison type meaning ID IS 1 (ID IS NOT DISTINCT FROM 1).

NULL_SAFE = 16

This is a flag meaning the comparison is null safe (meaning never returns NULL even if one operand is NULL). Only EQUAL and NOT_EQUAL are supported currently.

BIGGER = 2

The comparison type meaning > as in ID>1.

NOT_EQUAL_NULL_SAFE = 21

The comparison type meaning ID IS NOT 1 (ID IS DISTINCT FROM 1).

SMALLER_EQUAL = 3

The comparison type meaning <= as in ID<=1.

SMALLER = 4

The comparison type meaning < as in ID<1.

NOT_EQUAL = 5

The comparison type meaning <> as in ID<>1.

IS_NULL = 6

The comparison type meaning IS NULL as in NAME IS NULL.

IS_NOT_NULL = 7

The comparison type meaning IS NOT NULL as in NAME IS NOT NULL.

FALSE = 8

This is a pseudo comparison type that is only used for index conditions. It means the comparison will always yield FALSE. Example: 1=0.

IN_LIST = 9

This is a pseudo comparison type that is only used for index conditions. It means equals any value of a list. Example: IN(1, 2, 3).