public Boolean areColumnsUnique(ProjectRelBase rel, BitSet columns, boolean ignoreNulls) {
// ProjectRel maps a set of rows to a different set;
// Without knowledge of the mapping function(whether it
// preserves uniqueness), it is only safe to derive uniqueness
// info from the child of a project when the mapping is f(a) => a.
//
// Also need to map the input column set to the corresponding child
// references
List<RexNode> projExprs = rel.getProjects();
BitSet childColumns = new BitSet();
for (int bit : BitSets.toIter(columns)) {
RexNode projExpr = projExprs.get(bit);
if (projExpr instanceof RexInputRef) {
childColumns.set(((RexInputRef) projExpr).getIndex());
} else if (projExpr instanceof RexCall && ignoreNulls) {
// If the expression is a cast such that the types are the same
// except for the nullability, then if we're ignoring nulls,
// it doesn't matter whether the underlying column reference
// is nullable. Check that the types are the same by making a
// nullable copy of both types and then comparing them.
RexCall call = (RexCall) projExpr;
if (call.getOperator() != SqlStdOperatorTable.CAST) {
continue;
}
RexNode castOperand = call.getOperands().get(0);
if (!(castOperand instanceof RexInputRef)) {
continue;
}
RelDataTypeFactory typeFactory = rel.getCluster().getTypeFactory();
RelDataType castType = typeFactory.createTypeWithNullability(projExpr.getType(), true);
RelDataType origType = typeFactory.createTypeWithNullability(castOperand.getType(), true);
if (castType.equals(origType)) {
childColumns.set(((RexInputRef) castOperand).getIndex());
}
} else {
// If the expression will not influence uniqueness of the
// projection, then skip it.
continue;
}
}
// If no columns can affect uniqueness, then return unknown
if (childColumns.cardinality() == 0) {
return null;
}
return RelMetadataQuery.areColumnsUnique(rel.getChild(), childColumns, ignoreNulls);
}
private void reduceCasts(RexCall outerCast) {
RexNode[] operands = outerCast.getOperands();
if (operands.length != 1) {
return;
}
RelDataType outerCastType = outerCast.getType();
RelDataType operandType = operands[0].getType();
if (operandType.equals(outerCastType)) {
removableCasts.add(outerCast);
return;
}
// See if the reduction
// CAST((CAST x AS type) AS type NOT NULL)
// -> CAST(x AS type NOT NULL)
// applies. TODO jvs 15-Dec-2008: consider
// similar cases for precision changes.
if (!(operands[0] instanceof RexCall)) {
return;
}
RexCall innerCast = (RexCall) operands[0];
if (innerCast.getOperator() != SqlStdOperatorTable.castFunc) {
return;
}
if (innerCast.getOperands().length != 1) {
return;
}
RelDataTypeFactory typeFactory = preparingStmt.getFarragoTypeFactory();
RelDataType outerTypeNullable = typeFactory.createTypeWithNullability(outerCastType, true);
RelDataType innerTypeNullable = typeFactory.createTypeWithNullability(operandType, true);
if (outerTypeNullable != innerTypeNullable) {
return;
}
if (operandType.isNullable()) {
removableCasts.add(innerCast);
}
}
/**
* Creates a record type with specified field names.
*
* <p>The array of field names may be null, or any of the names within it can be null. We
* recommend using explicit names where possible, because it makes it much easier to figure out
* the intent of fields when looking at planner output.
*
* @param typeFactory Type factory
* @param exprs Expressions
* @param names Field names, may be null, or elements may be null
* @return Record type
*/
public static RelDataType createStructType(
RelDataTypeFactory typeFactory, final RexNode[] exprs, final String[] names) {
return typeFactory.createStructType(
new RelDataTypeFactory.FieldInfo() {
public int getFieldCount() {
return exprs.length;
}
public String getFieldName(int index) {
if (names == null) {
return "$f" + index;
}
final String name = names[index];
if (name == null) {
return "$f" + index;
}
return name;
}
public RelDataType getFieldType(int index) {
return exprs[index].getType();
}
});
}
/** Initializes this catalog reader. */
protected void init() {
final RelDataType intType = typeFactory.createSqlType(SqlTypeName.INTEGER);
final RelDataType varchar10Type = typeFactory.createSqlType(SqlTypeName.VARCHAR, 10);
final RelDataType varchar20Type = typeFactory.createSqlType(SqlTypeName.VARCHAR, 20);
final RelDataType timestampType = typeFactory.createSqlType(SqlTypeName.TIMESTAMP);
final RelDataType booleanType = typeFactory.createSqlType(SqlTypeName.BOOLEAN);
final RelDataType rectilinearCoordType =
typeFactory.createStructType(new RelDataType[] {intType, intType}, new String[] {"X", "Y"});
// TODO jvs 12-Feb-2005: register this canonical instance with type
// factory
addressType =
new ObjectSqlType(
SqlTypeName.STRUCTURED,
new SqlIdentifier("ADDRESS", SqlParserPos.ZERO),
false,
Arrays.asList(
new RelDataTypeFieldImpl("STREET", 0, varchar20Type),
new RelDataTypeFieldImpl("CITY", 1, varchar20Type),
new RelDataTypeFieldImpl("ZIP", 1, intType),
new RelDataTypeFieldImpl("STATE", 1, varchar20Type)),
RelDataTypeComparability.None);
// Register "SALES" schema.
MockSchema salesSchema = new MockSchema("SALES");
registerSchema(salesSchema);
// Register "EMP" table.
MockTable empTable = new MockTable(this, salesSchema, "EMP");
empTable.addColumn("EMPNO", intType);
empTable.addColumn("ENAME", varchar20Type);
empTable.addColumn("JOB", varchar10Type);
empTable.addColumn("MGR", intType);
empTable.addColumn("HIREDATE", timestampType);
empTable.addColumn("SAL", intType);
empTable.addColumn("COMM", intType);
empTable.addColumn("DEPTNO", intType);
empTable.addColumn("SLACKER", booleanType);
registerTable(empTable);
// Register "DEPT" table.
MockTable deptTable = new MockTable(this, salesSchema, "DEPT");
deptTable.addColumn("DEPTNO", intType);
deptTable.addColumn("NAME", varchar10Type);
registerTable(deptTable);
// Register "BONUS" table.
MockTable bonusTable = new MockTable(this, salesSchema, "BONUS");
bonusTable.addColumn("ENAME", varchar20Type);
bonusTable.addColumn("JOB", varchar10Type);
bonusTable.addColumn("SAL", intType);
bonusTable.addColumn("COMM", intType);
registerTable(bonusTable);
// Register "SALGRADE" table.
MockTable salgradeTable = new MockTable(this, salesSchema, "SALGRADE");
salgradeTable.addColumn("GRADE", intType);
salgradeTable.addColumn("LOSAL", intType);
salgradeTable.addColumn("HISAL", intType);
registerTable(salgradeTable);
// Register "EMP_ADDRESS" table
MockTable contactAddressTable = new MockTable(this, salesSchema, "EMP_ADDRESS");
contactAddressTable.addColumn("EMPNO", intType);
contactAddressTable.addColumn("HOME_ADDRESS", addressType);
contactAddressTable.addColumn("MAILING_ADDRESS", addressType);
registerTable(contactAddressTable);
// Register "CUSTOMER" schema.
MockSchema customerSchema = new MockSchema("CUSTOMER");
registerSchema(customerSchema);
// Register "CONTACT" table.
MockTable contactTable = new MockTable(this, customerSchema, "CONTACT");
contactTable.addColumn("CONTACTNO", intType);
contactTable.addColumn("FNAME", varchar10Type);
contactTable.addColumn("LNAME", varchar10Type);
contactTable.addColumn("EMAIL", varchar20Type);
contactTable.addColumn("COORD", rectilinearCoordType);
registerTable(contactTable);
// Register "ACCOUNT" table.
MockTable accountTable = new MockTable(this, customerSchema, "ACCOUNT");
accountTable.addColumn("ACCTNO", intType);
accountTable.addColumn("TYPE", varchar20Type);
accountTable.addColumn("BALANCE", intType);
registerTable(accountTable);
}
public void onRegister(RelDataTypeFactory typeFactory) {
rowType = typeFactory.createStructType(columnList);
collationList = deduceMonotonicity(this);
}
