| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package org.apache.druid.sql.calcite.expression.builtin; |
| |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import org.apache.calcite.rex.RexNode; |
| import org.apache.calcite.sql.SqlFunction; |
| import org.apache.calcite.sql.SqlFunctionCategory; |
| import org.apache.calcite.sql.SqlOperator; |
| import org.apache.calcite.sql.type.SqlTypeFamily; |
| import org.apache.calcite.sql.type.SqlTypeName; |
| import org.apache.druid.java.util.common.IAE; |
| import org.apache.druid.java.util.common.StringUtils; |
| import org.apache.druid.math.expr.Expr; |
| import org.apache.druid.math.expr.Parser; |
| import org.apache.druid.segment.column.RowSignature; |
| import org.apache.druid.sql.calcite.expression.DruidExpression; |
| import org.apache.druid.sql.calcite.expression.OperatorConversions; |
| import org.apache.druid.sql.calcite.expression.SqlOperatorConversion; |
| import org.apache.druid.sql.calcite.planner.PlannerContext; |
| import org.joda.time.Period; |
| |
| import java.util.Map; |
| |
| /** |
| * DATE_TRUNC function similar to PostgreSQL. |
| */ |
| public class DateTruncOperatorConversion implements SqlOperatorConversion |
| { |
| private static final Map<String, Period> TRUNC_PERIOD_MAP = |
| ImmutableMap.<String, Period>builder() |
| .put("microseconds", Period.millis(1)) // We don't support microsecond precision, so millis is fine. |
| .put("milliseconds", Period.millis(1)) |
| .put("second", Period.seconds(1)) |
| .put("minute", Period.minutes(1)) |
| .put("hour", Period.hours(1)) |
| .put("day", Period.days(1)) |
| .put("week", Period.weeks(1)) |
| .put("month", Period.months(1)) |
| .put("quarter", Period.months(3)) |
| .put("year", Period.years(1)) |
| .put("decade", Period.years(10)) |
| .put("century", Period.years(100)) |
| .put("millennium", Period.years(1000)) |
| .build(); |
| |
| |
| private static final SqlFunction SQL_FUNCTION = OperatorConversions |
| .operatorBuilder("DATE_TRUNC") |
| .operandTypes(SqlTypeFamily.CHARACTER, SqlTypeFamily.TIMESTAMP) |
| .requiredOperands(2) |
| .returnTypeNonNull(SqlTypeName.TIMESTAMP) |
| .functionCategory(SqlFunctionCategory.TIMEDATE) |
| .build(); |
| |
| @Override |
| public SqlOperator calciteOperator() |
| { |
| return SQL_FUNCTION; |
| } |
| |
| @Override |
| public DruidExpression toDruidExpression( |
| final PlannerContext plannerContext, |
| final RowSignature rowSignature, |
| final RexNode rexNode |
| ) |
| { |
| return OperatorConversions.convertCall( |
| plannerContext, |
| rowSignature, |
| rexNode, |
| inputExpressions -> { |
| final DruidExpression arg = inputExpressions.get(1); |
| final Expr truncTypeExpr = Parser.parse( |
| inputExpressions.get(0).getExpression(), |
| plannerContext.getExprMacroTable() |
| ); |
| |
| if (!truncTypeExpr.isLiteral()) { |
| throw new IAE("Operator[%s] truncType must be a literal", calciteOperator().getName()); |
| } |
| |
| final String truncType = (String) truncTypeExpr.getLiteralValue(); |
| final Period truncPeriod = TRUNC_PERIOD_MAP.get(StringUtils.toLowerCase(truncType)); |
| |
| if (truncPeriod == null) { |
| throw new IAE("Operator[%s] cannot truncate to[%s]", calciteOperator().getName(), truncType); |
| } |
| |
| return DruidExpression.fromFunctionCall( |
| "timestamp_floor", |
| ImmutableList.of( |
| arg, |
| DruidExpression.fromExpression(DruidExpression.stringLiteral(truncPeriod.toString())), |
| DruidExpression.fromExpression(DruidExpression.stringLiteral(null)), |
| DruidExpression.fromExpression(DruidExpression.stringLiteral(plannerContext.getTimeZone().getID())) |
| ) |
| ); |
| } |
| ); |
| } |
| } |