private RelOptTableImpl getTableFrom(List<String> names, List<String> schemaNames) {
OptiqSchema schema = getSchema(Iterables.concat(schemaNames, Util.skipLast(names)));
if (schema == null) {
return null;
}
final String name = Util.last(names);
Pair<String, Table> pair = schema.getTable(name, caseSensitive);
if (pair == null) {
pair = schema.getTableBasedOnNullaryFunction(name, caseSensitive);
}
if (pair != null) {
final Table table = pair.getValue();
final String name2 = pair.getKey();
return RelOptTableImpl.create(this, table.getRowType(typeFactory), schema.add(name2, table));
}
return null;
}
/**
* Derives an alias for a node, and invents a mangled identifier if it cannot.
*
* <p>Examples:
*
* <ul>
* <li>Alias: "1 + 2 as foo" yields "foo"
* <li>Identifier: "foo.bar.baz" yields "baz"
* <li>Anything else yields "expr$<i>ordinal</i>"
* </ul>
*
* @return An alias, if one can be derived; or a synthetic alias "expr$<i>ordinal</i>" if ordinal
* >= 0; otherwise null
*/
public static String getAlias(SqlNode node, int ordinal) {
switch (node.getKind()) {
case AS:
// E.g. "1 + 2 as foo" --> "foo"
return ((SqlCall) node).getOperands()[1].toString();
case OVER:
// E.g. "bids over w" --> "bids"
return getAlias(((SqlCall) node).getOperands()[0], ordinal);
case IDENTIFIER:
// E.g. "foo.bar" --> "bar"
return Util.last(((SqlIdentifier) node).names);
default:
if (ordinal < 0) {
return null;
} else {
return SqlUtil.deriveAliasFromOrdinal(ordinal);
}
}
}
private Collection<Function> getFunctionsFrom(List<String> names) {
final List<Function> functions2 = Lists.newArrayList();
final List<? extends List<String>> schemaNameList;
if (names.size() > 1) {
// If name is qualified, ignore path.
schemaNameList = ImmutableList.of(ImmutableList.<String>of());
} else {
OptiqSchema schema = getSchema(defaultSchema);
if (schema == null) {
schemaNameList = ImmutableList.of();
} else {
schemaNameList = schema.getPath();
}
}
for (List<String> schemaNames : schemaNameList) {
OptiqSchema schema = getSchema(Iterables.concat(schemaNames, Util.skipLast(names)));
if (schema != null) {
final String name = Util.last(names);
functions2.addAll(schema.getFunctions(name, true));
}
}
return functions2;
}