public RelOptTableImpl getTable(final String[] names) {
List<Pair<String, Object>> pairs = new ArrayList<Pair<String, Object>>();
Schema schema2 = schema;
for (int i = 0; i < names.length; i++) {
final String name = names[i];
Schema subSchema = schema2.getSubSchema(name);
if (subSchema != null) {
pairs.add(Pair.<String, Object>of(name, subSchema));
schema2 = subSchema;
continue;
}
final Table table = schema2.getTable(name);
if (table != null) {
pairs.add(Pair.<String, Object>of(name, table));
if (i != names.length - 1) {
// not enough objects to match all names
return null;
}
return new RelOptTableImpl(
this, typeFactory.createType(table.getElementType()), names, table);
}
return null;
}
return null;
}
/** Returns the root schema. */
public static Schema root(Schema schema) {
for (Schema s = schema; ; ) {
Schema previous = s;
s = s.getParentSchema();
if (s == null) {
return previous;
}
}
}
/** Returns the path of a schema, appending the name of a table if not null. */
public static List<String> path(Schema schema, String name) {
final List<String> list = new ArrayList<String>();
if (name != null) {
list.add(name);
}
for (Schema s = schema; s != null; s = s.getParentSchema()) {
if (s.getParentSchema() != null || !s.getName().equals("")) {
// Omit the root schema's name from the path if it's the empty string,
// which it usually is.
list.add(s.getName());
}
}
return ImmutableList.copyOf(Lists.reverse(list));
}
/** Returns the expression to access a table within a schema. */
public static Expression tableExpression(
Schema schema, Type elementType, String tableName, Class clazz) {
final MethodCallExpression expression;
if (Table.class.isAssignableFrom(clazz)) {
expression =
Expressions.call(
schema.getExpression(),
BuiltinMethod.SCHEMA_GET_TABLE.method,
Expressions.constant(tableName));
} else {
expression =
Expressions.call(
BuiltinMethod.SCHEMAS_QUERYABLE.method,
DataContext.ROOT,
schema.getExpression(),
Expressions.constant(elementType),
Expressions.constant(tableName));
}
return Types.castIfNecessary(clazz, expression);
}
public List<SqlOperator> lookupOperatorOverloads(
SqlIdentifier opName, SqlFunctionCategory category, SqlSyntax syntax) {
if (syntax != SqlSyntax.Function) {
return Collections.emptyList();
}
// FIXME: ignoring prefix of opName
String name = opName.names[opName.names.length - 1];
List<TableFunction> tableFunctions = rootSchema.getTableFunctions(name);
if (tableFunctions.isEmpty()) {
return Collections.emptyList();
}
return toOps(name, tableFunctions);
}
/** Returns the expression for a sub-schema. */
public static Expression subSchemaExpression(Schema schema, String name, Class type) {
// (Type) schemaExpression.getSubSchema("name")
Expression call =
Expressions.call(
schema.getExpression(),
BuiltinMethod.SCHEMA_GET_SUB_SCHEMA.method,
Expressions.constant(name));
// CHECKSTYLE: IGNORE 2
//noinspection unchecked
if (false && type != null && !type.isAssignableFrom(Schema.class)) {
return unwrap(call, type);
}
return call;
}
@Override
protected PreparedExecution implement(
RelDataType rowType,
RelNode rootRel,
SqlKind sqlKind,
ClassDeclaration decl,
Argument[] args) {
RelDataType resultType = rootRel.getRowType();
boolean isDml = sqlKind.belongsTo(SqlKind.DML);
javaCompiler = createCompiler();
EnumerableRelImplementor relImplementor =
getRelImplementor(rootRel.getCluster().getRexBuilder());
BlockExpression expr = relImplementor.implementRoot((EnumerableRel) rootRel);
ParameterExpression root0 = Expressions.parameter(DataContext.class, "root0");
String s =
Expressions.toString(
Blocks.create(
Expressions.declare(
Modifier.FINAL, (ParameterExpression) schema.getExpression(), root0),
expr),
false);
final Executable executable;
try {
executable =
(Executable)
ExpressionEvaluator.createFastScriptEvaluator(
s, Executable.class, new String[] {root0.name});
} catch (Exception e) {
throw Helper.INSTANCE.wrap("Error while compiling generated Java code:\n" + s, e);
}
if (timingTracer != null) {
timingTracer.traceTime("end codegen");
}
if (timingTracer != null) {
timingTracer.traceTime("end compilation");
}
return new PreparedExecution(
null, rootRel, resultType, isDml, mapTableModOp(isDml, sqlKind), null) {
public Object execute() {
return executable.execute(schema);
}
};
}