/** Ensures that a type's nullability matches a value's nullability. */
public RelDataType matchNullability(RelDataType type, RexNode value) {
boolean typeNullability = type.isNullable();
boolean valueNullability = value.getType().isNullable();
if (typeNullability != valueNullability) {
return getTypeFactory().createTypeWithNullability(type, valueNullability);
}
return type;
}
/**
* Makes an expression which converts a value of type T to a value of type T NOT NULL, or throws
* if the value is NULL. If the expression is already NOT NULL, does nothing.
*/
public RexNode makeNotNullCast(RexNode expr) {
RelDataType type = expr.getType();
if (!type.isNullable()) {
return expr;
}
RelDataType typeNotNull = getTypeFactory().createTypeWithNullability(type, false);
return new RexCall(typeNotNull, SqlStdOperatorTable.CAST, ImmutableList.of(expr));
}
public Type getJavaClass(RelDataType type) {
if (type instanceof JavaType) {
JavaType javaType = (JavaType) type;
return javaType.getJavaClass();
}
if (type.isStruct() && type.getFieldCount() == 1) {
return getJavaClass(type.getFieldList().get(0).getType());
}
if (type instanceof BasicSqlType || type instanceof IntervalSqlType) {
switch (type.getSqlTypeName()) {
case VARCHAR:
case CHAR:
return String.class;
case DATE:
case TIME:
case INTEGER:
case INTERVAL_YEAR_MONTH:
return type.isNullable() ? Integer.class : int.class;
case TIMESTAMP:
case BIGINT:
case INTERVAL_DAY_TIME:
return type.isNullable() ? Long.class : long.class;
case SMALLINT:
return type.isNullable() ? Short.class : short.class;
case TINYINT:
return type.isNullable() ? Byte.class : byte.class;
case DECIMAL:
return BigDecimal.class;
case BOOLEAN:
return type.isNullable() ? Boolean.class : boolean.class;
case DOUBLE:
case FLOAT: // sic
return type.isNullable() ? Double.class : double.class;
case REAL:
return type.isNullable() ? Float.class : float.class;
case BINARY:
case VARBINARY:
return ByteString.class;
case ARRAY:
return Array.class;
case ANY:
return Object.class;
}
}
switch (type.getSqlTypeName()) {
case ROW:
assert type instanceof RelRecordType;
if (type instanceof JavaRecordType) {
return ((JavaRecordType) type).clazz;
} else {
return createSyntheticType((RelRecordType) type);
}
case MAP:
return Map.class;
case ARRAY:
case MULTISET:
return List.class;
}
return null;
}
public RelDataType toSql(RelDataType type) {
if (type instanceof RelRecordType) {
return createStructType(
Lists.transform(
type.getFieldList(),
new Function<RelDataTypeField, RelDataType>() {
public RelDataType apply(RelDataTypeField a0) {
return toSql(a0.getType());
}
}),
type.getFieldNames());
}
if (type instanceof JavaType) {
return createTypeWithNullability(createSqlType(type.getSqlTypeName()), type.isNullable());
}
return type;
}
/**
* Creates a literal of a given type. The value is assumed to be compatible with the type.
*
* @param value Value
* @param type Type
* @param allowCast Whether to allow a cast. If false, value is always a {@link RexLiteral} but
* may not be the exact type
* @return Simple literal, or cast simple literal
*/
public RexNode makeLiteral(Object value, RelDataType type, boolean allowCast) {
if (value == null) {
return makeCast(type, constantNull);
}
if (type.isNullable()) {
final RelDataType typeNotNull = typeFactory.createTypeWithNullability(type, false);
RexNode literalNotNull = makeLiteral(value, typeNotNull, allowCast);
return makeAbstractCast(type, literalNotNull);
}
value = clean(value, type);
RexLiteral literal;
final List<RexNode> operands;
switch (type.getSqlTypeName()) {
case CHAR:
return makeCharLiteral(padRight((NlsString) value, type.getPrecision()));
case VARCHAR:
literal = makeCharLiteral((NlsString) value);
if (allowCast) {
return makeCast(type, literal);
} else {
return literal;
}
case BINARY:
return makeBinaryLiteral(padRight((ByteString) value, type.getPrecision()));
case VARBINARY:
literal = makeBinaryLiteral((ByteString) value);
if (allowCast) {
return makeCast(type, literal);
} else {
return literal;
}
case TINYINT:
case SMALLINT:
case INTEGER:
case BIGINT:
case DECIMAL:
return makeExactLiteral((BigDecimal) value, type);
case FLOAT:
case REAL:
case DOUBLE:
return makeApproxLiteral((BigDecimal) value, type);
case BOOLEAN:
return (Boolean) value ? booleanTrue : booleanFalse;
case TIME:
return makeTimeLiteral((Calendar) value, type.getPrecision());
case DATE:
return makeDateLiteral((Calendar) value);
case TIMESTAMP:
return makeTimestampLiteral((Calendar) value, type.getPrecision());
case INTERVAL_YEAR_MONTH:
case INTERVAL_DAY_TIME:
return makeIntervalLiteral((BigDecimal) value, type.getIntervalQualifier());
case MAP:
final MapSqlType mapType = (MapSqlType) type;
@SuppressWarnings("unchecked")
final Map<Object, Object> map = (Map) value;
operands = new ArrayList<RexNode>();
for (Map.Entry<Object, Object> entry : map.entrySet()) {
operands.add(makeLiteral(entry.getKey(), mapType.getKeyType(), allowCast));
operands.add(makeLiteral(entry.getValue(), mapType.getValueType(), allowCast));
}
return makeCall(SqlStdOperatorTable.MAP_VALUE_CONSTRUCTOR, operands);
case ARRAY:
final ArraySqlType arrayType = (ArraySqlType) type;
@SuppressWarnings("unchecked")
final List<Object> listValue = (List) value;
operands = new ArrayList<RexNode>();
for (Object entry : listValue) {
operands.add(makeLiteral(entry, arrayType.getComponentType(), allowCast));
}
return makeCall(SqlStdOperatorTable.ARRAY_VALUE_CONSTRUCTOR, operands);
case ANY:
return makeLiteral(value, guessType(value), allowCast);
default:
throw Util.unexpected(type.getSqlTypeName());
}
}
/**
* Creates a reference to all the fields in the row.
*
* <p>For example, if the input row has type <code>T{f0,f1,f2,f3,f4}</code> then <code>
* makeRangeReference(T{f0,f1,f2,f3,f4}, S{f3,f4}, 3)</code> is an expression which yields the
* last 2 fields.
*
* @param type Type of the resulting range record.
* @param offset Index of first field.
* @param nullable Whether the record is nullable.
*/
public RexRangeRef makeRangeReference(RelDataType type, int offset, boolean nullable) {
if (nullable && !type.isNullable()) {
type = typeFactory.createTypeWithNullability(type, nullable);
}
return new RexRangeRef(type, offset);
}
