// implement RelDataType
public SqlIdentifier getSqlIdentifier() {
SqlTypeName typeName = getSqlTypeName();
if (typeName == null) {
return null;
}
return new SqlIdentifier(typeName.name(), SqlParserPos.ZERO);
}
public boolean canCastFrom(SqlTypeName to, SqlTypeName from, boolean coerce) {
assert (null != to);
assert (null != from);
Map<SqlTypeName, Set<SqlTypeName>> ruleset = coerce ? coerceRules : rules;
if (to.equals(SqlTypeName.NULL)) {
return false;
} else if (from.equals(SqlTypeName.NULL)) {
return true;
}
Set<SqlTypeName> rule = ruleset.get(to);
if (null == rule) {
// if you hit this assert, see the constructor of this class on how
// to add new rule
throw Util.newInternal("No assign rules for " + to + " defined");
}
return rule.contains(from);
}
<T> PrepareResult<T> prepare_(
Context context, String sql, Queryable<T> queryable, Type elementType) {
final JavaTypeFactory typeFactory = context.getTypeFactory();
OptiqCatalogReader catalogReader = new OptiqCatalogReader(context.getRootSchema(), typeFactory);
final OptiqPreparingStmt preparingStmt =
new OptiqPreparingStmt(catalogReader, typeFactory, context.getRootSchema());
preparingStmt.setResultCallingConvention(CallingConvention.ENUMERABLE);
final RelDataType x;
final PreparedResult preparedResult;
if (sql != null) {
assert queryable == null;
SqlParser parser = new SqlParser(sql);
SqlNode sqlNode;
try {
sqlNode = parser.parseQuery();
} catch (SqlParseException e) {
throw new RuntimeException("parse failed", e);
}
final Schema rootSchema = context.getRootSchema();
SqlValidator validator =
new SqlValidatorImpl(
new ChainedSqlOperatorTable(
Arrays.<SqlOperatorTable>asList(
SqlStdOperatorTable.instance(),
new MySqlOperatorTable(rootSchema, typeFactory))),
catalogReader,
typeFactory,
SqlConformance.Default) {};
preparedResult = preparingStmt.prepareSql(sqlNode, Object.class, validator, true);
x = validator.getValidatedNodeType(sqlNode);
} else {
assert queryable != null;
x = context.getTypeFactory().createType(elementType);
preparedResult = preparingStmt.prepareQueryable(queryable, x);
}
// TODO: parameters
final List<Parameter> parameters = Collections.emptyList();
// TODO: column meta data
final List<ColumnMetaData> columns = new ArrayList<ColumnMetaData>();
RelDataType jdbcType = makeStruct(typeFactory, x);
for (RelDataTypeField field : jdbcType.getFields()) {
RelDataType type = field.getType();
SqlTypeName sqlTypeName = type.getSqlTypeName();
columns.add(
new ColumnMetaData(
columns.size(),
false,
true,
false,
false,
type.isNullable() ? 1 : 0,
true,
0,
field.getName(),
field.getName(),
null,
sqlTypeName.allowsPrec() && false ? type.getPrecision() : -1,
sqlTypeName.allowsScale() ? type.getScale() : -1,
null,
null,
sqlTypeName.getJdbcOrdinal(),
sqlTypeName.getName(),
true,
false,
false,
null));
}
return new PrepareResult<T>(sql, parameters, columns, (Enumerable<T>) preparedResult.execute());
}