viirya commented on a change in pull request #29565: URL: https://github.com/apache/spark/pull/29565#discussion_r478842634
########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` + */ +object UnwrapCast extends Rule[LogicalPlan] { + override def apply(plan: LogicalPlan): LogicalPlan = plan transform { + case l: LogicalPlan => l transformExpressionsUp { + case e @ BinaryComparison(_, _) => unwrapCast(e) + } + } + + private def unwrapCast(exp: Expression): Expression = exp match { Review comment: This method is too long. Can we separate it to few smaller methods for better readability? ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler Review comment: nit: optimizes ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` + */ +object UnwrapCast extends Rule[LogicalPlan] { + override def apply(plan: LogicalPlan): LogicalPlan = plan transform { + case l: LogicalPlan => l transformExpressionsUp { + case e @ BinaryComparison(_, _) => unwrapCast(e) + } + } Review comment: If this rule targets predicate pushdown, shall we only capture the pattern `PhysicalOperation`? ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` Review comment: Before I read the code below, I don't know what this doc means. Can you revise the example of "replaces the cast with different simpler constructs" a little? For example, `max` is ambiguous, actually it means the maximum value of `fromType`. ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` + */ +object UnwrapCast extends Rule[LogicalPlan] { + override def apply(plan: LogicalPlan): LogicalPlan = plan transform { + case l: LogicalPlan => l transformExpressionsUp { + case e @ BinaryComparison(_, _) => unwrapCast(e) + } + } + + private def unwrapCast(exp: Expression): Expression = exp match { + case BinaryComparison(Literal(_, _), Cast(_, _, _)) => + def swap(e: Expression): Expression = e match { + case GreaterThan(left, right) => LessThan(right, left) + case GreaterThanOrEqual(left, right) => LessThanOrEqual(right, left) + case EqualTo(left, right) => EqualTo(right, left) + case EqualNullSafe(left, right) => EqualNullSafe(right, left) + case LessThanOrEqual(left, right) => GreaterThanOrEqual(right, left) + case LessThan(left, right) => GreaterThan(right, left) + case other => other + } + swap(unwrapCast(swap(exp))) + + case BinaryComparison(Cast(fromExp, _, _), Literal(value, toType)) => + val fromType = fromExp.dataType + if (!fromType.isInstanceOf[IntegralType] || !toType.isInstanceOf[IntegralType] + || !Cast.canUpCast(fromType, toType)) { + return exp + } + + // Check if the literal value is within the range of the `fromType`, and handle the boundary + // cases in the following + val toIntegralType = toType.asInstanceOf[IntegralType] + val (min, max) = getRange(fromType) + val (minInToType, maxInToType) = + (Cast(Literal(min), toType).eval(), Cast(Literal(max), toType).eval()) + + // Compare upper bounds + val maxCmp = toIntegralType.ordering.asInstanceOf[Ordering[Any]].compare(value, maxInToType) + if (maxCmp > 0) { Review comment: For each of case, can we add few comment explaining what we're going to do. E.g., ```scala // Because `value` is larger than maximum value of `fromType`, we can simplify binary comparison, e.g., non-null `fromExp` can never equal to `value`. if (maxCmp > 0) { ... } ``` ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` + */ +object UnwrapCast extends Rule[LogicalPlan] { + override def apply(plan: LogicalPlan): LogicalPlan = plan transform { + case l: LogicalPlan => l transformExpressionsUp { + case e @ BinaryComparison(_, _) => unwrapCast(e) + } + } + + private def unwrapCast(exp: Expression): Expression = exp match { + case BinaryComparison(Literal(_, _), Cast(_, _, _)) => + def swap(e: Expression): Expression = e match { + case GreaterThan(left, right) => LessThan(right, left) + case GreaterThanOrEqual(left, right) => LessThanOrEqual(right, left) + case EqualTo(left, right) => EqualTo(right, left) + case EqualNullSafe(left, right) => EqualNullSafe(right, left) + case LessThanOrEqual(left, right) => GreaterThanOrEqual(right, left) + case LessThan(left, right) => GreaterThan(right, left) + case other => other + } + swap(unwrapCast(swap(exp))) + + case BinaryComparison(Cast(fromExp, _, _), Literal(value, toType)) => + val fromType = fromExp.dataType + if (!fromType.isInstanceOf[IntegralType] || !toType.isInstanceOf[IntegralType] + || !Cast.canUpCast(fromType, toType)) { + return exp + } + + // Check if the literal value is within the range of the `fromType`, and handle the boundary + // cases in the following + val toIntegralType = toType.asInstanceOf[IntegralType] + val (min, max) = getRange(fromType) + val (minInToType, maxInToType) = + (Cast(Literal(min), toType).eval(), Cast(Literal(max), toType).eval()) + + // Compare upper bounds + val maxCmp = toIntegralType.ordering.asInstanceOf[Ordering[Any]].compare(value, maxInToType) + if (maxCmp > 0) { + exp match { + case EqualTo(_, _) | GreaterThan(_, _) | GreaterThanOrEqual(_, _) => + return falseIfNotNull(fromExp) + case LessThan(_, _) | LessThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case EqualNullSafe(_, _) => + return FalseLiteral + case _ => return exp // impossible but safe guard, same below + } + } else if (maxCmp == 0) { + exp match { + case GreaterThan(_, _) => + return falseIfNotNull(fromExp) + case LessThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case LessThan(_, _) => + return Not(EqualTo(fromExp, Literal(max, fromType))) + case GreaterThanOrEqual(_, _) | EqualTo(_, _) | EqualNullSafe(_, _) => + return EqualTo(fromExp, Literal(max, fromType)) + case _ => return exp + } + } + + // Compare lower bounds + val minCmp = toIntegralType.ordering.asInstanceOf[Ordering[Any]].compare(value, minInToType) + if (minCmp < 0) { + exp match { + case GreaterThan(_, _) | GreaterThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case LessThan(_, _) | LessThanOrEqual(_, _) | EqualTo(_, _) => + return falseIfNotNull(fromExp) + case EqualNullSafe(_, _) => + return FalseLiteral + case _ => return exp + } + } else if (minCmp == 0) { + exp match { + case LessThan(_, _) => + return falseIfNotNull(fromExp) + case GreaterThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case GreaterThan(_, _) => + return Not(EqualTo(fromExp, Literal(min, fromType))) + case LessThanOrEqual(_, _) | EqualTo(_, _) | EqualNullSafe(_, _) => + return EqualTo(fromExp, Literal(min, fromType)) + case _ => return exp + } + } + + // Now we can assume `value` is within the bound of the source type, e.g., min < value < max + val lit = Cast(Literal(value), fromType) + exp match { + case GreaterThan(_, _) => GreaterThan(fromExp, lit) + case GreaterThanOrEqual(_, _) => GreaterThanOrEqual(fromExp, lit) + case EqualTo(_, _) => EqualTo(fromExp, lit) + case EqualNullSafe(_, _) => EqualNullSafe(fromExp, lit) + case LessThan(_, _) => LessThan(fromExp, lit) + case LessThanOrEqual(_, _) => LessThanOrEqual(fromExp, lit) + } + + case _ => exp + } + + private[sql] def falseIfNotNull(e: Expression): Expression = + And(IsNull(e), Literal(null, BooleanType)) + + private[sql] def trueIfNotNull(e: Expression): Expression = + Or(IsNotNull(e), Literal(null, BooleanType)) Review comment: ditto. ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` Review comment: Is this actually `BinaryComparison(Cast(fromExp, toType), Literal(value, toType))`? That's said `Cast` and `Literal` must be same type. ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` Review comment: `Cast(fromExp, fromType)` -> `Cast(fromExp, toType)`? ########## File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/UnwrapCast.scala ########## @@ -0,0 +1,155 @@ +/* + * 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.spark.sql.catalyst.optimizer + +import org.apache.spark.sql.catalyst.expressions._ +import org.apache.spark.sql.catalyst.expressions.Literal.FalseLiteral +import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan +import org.apache.spark.sql.catalyst.rules.Rule +import org.apache.spark.sql.types._ + +/** + * Unwrap casts in binary comparison operations with the following pattern: + * `BinaryComparison(Cast(fromExp, _), Literal(value, toType))` + * This rule optimize expressions with this pattern by either replacing the cast with simpler + * constructs, or moving the cast from the expression side to the literal side, so they can be + * optimized away and pushed down to data sources. + * + * Currently this only handles the case where `fromType` (of `fromExp`) and `toType` are of + * integral types (i.e., byte, short, int and long). It checks to see if the literal `value` is + * within range (min, max) of the `fromType`. If this is true then it means we can safely cast the + * `value` to the `fromType` and thus able to move the cast to the literal side. Otherwise, it + * replaces the cast with different simpler constructs, such as + * `EqualTo(fromExp, Literal(max, fromType)` when input is + * `GreaterThanOrEqualTo(Cast(fromExp, fromType), Literal(max, toType))` + */ +object UnwrapCast extends Rule[LogicalPlan] { + override def apply(plan: LogicalPlan): LogicalPlan = plan transform { + case l: LogicalPlan => l transformExpressionsUp { + case e @ BinaryComparison(_, _) => unwrapCast(e) + } + } + + private def unwrapCast(exp: Expression): Expression = exp match { + case BinaryComparison(Literal(_, _), Cast(_, _, _)) => + def swap(e: Expression): Expression = e match { + case GreaterThan(left, right) => LessThan(right, left) + case GreaterThanOrEqual(left, right) => LessThanOrEqual(right, left) + case EqualTo(left, right) => EqualTo(right, left) + case EqualNullSafe(left, right) => EqualNullSafe(right, left) + case LessThanOrEqual(left, right) => GreaterThanOrEqual(right, left) + case LessThan(left, right) => GreaterThan(right, left) + case other => other + } + swap(unwrapCast(swap(exp))) + + case BinaryComparison(Cast(fromExp, _, _), Literal(value, toType)) => + val fromType = fromExp.dataType + if (!fromType.isInstanceOf[IntegralType] || !toType.isInstanceOf[IntegralType] + || !Cast.canUpCast(fromType, toType)) { + return exp + } + + // Check if the literal value is within the range of the `fromType`, and handle the boundary + // cases in the following + val toIntegralType = toType.asInstanceOf[IntegralType] + val (min, max) = getRange(fromType) + val (minInToType, maxInToType) = + (Cast(Literal(min), toType).eval(), Cast(Literal(max), toType).eval()) + + // Compare upper bounds + val maxCmp = toIntegralType.ordering.asInstanceOf[Ordering[Any]].compare(value, maxInToType) + if (maxCmp > 0) { + exp match { + case EqualTo(_, _) | GreaterThan(_, _) | GreaterThanOrEqual(_, _) => + return falseIfNotNull(fromExp) + case LessThan(_, _) | LessThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case EqualNullSafe(_, _) => + return FalseLiteral + case _ => return exp // impossible but safe guard, same below + } + } else if (maxCmp == 0) { + exp match { + case GreaterThan(_, _) => + return falseIfNotNull(fromExp) + case LessThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case LessThan(_, _) => + return Not(EqualTo(fromExp, Literal(max, fromType))) + case GreaterThanOrEqual(_, _) | EqualTo(_, _) | EqualNullSafe(_, _) => + return EqualTo(fromExp, Literal(max, fromType)) + case _ => return exp + } + } + + // Compare lower bounds + val minCmp = toIntegralType.ordering.asInstanceOf[Ordering[Any]].compare(value, minInToType) + if (minCmp < 0) { + exp match { + case GreaterThan(_, _) | GreaterThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case LessThan(_, _) | LessThanOrEqual(_, _) | EqualTo(_, _) => + return falseIfNotNull(fromExp) + case EqualNullSafe(_, _) => + return FalseLiteral + case _ => return exp + } + } else if (minCmp == 0) { + exp match { + case LessThan(_, _) => + return falseIfNotNull(fromExp) + case GreaterThanOrEqual(_, _) => + return trueIfNotNull(fromExp) + case GreaterThan(_, _) => + return Not(EqualTo(fromExp, Literal(min, fromType))) + case LessThanOrEqual(_, _) | EqualTo(_, _) | EqualNullSafe(_, _) => + return EqualTo(fromExp, Literal(min, fromType)) + case _ => return exp + } + } + + // Now we can assume `value` is within the bound of the source type, e.g., min < value < max + val lit = Cast(Literal(value), fromType) + exp match { + case GreaterThan(_, _) => GreaterThan(fromExp, lit) + case GreaterThanOrEqual(_, _) => GreaterThanOrEqual(fromExp, lit) + case EqualTo(_, _) => EqualTo(fromExp, lit) + case EqualNullSafe(_, _) => EqualNullSafe(fromExp, lit) + case LessThan(_, _) => LessThan(fromExp, lit) + case LessThanOrEqual(_, _) => LessThanOrEqual(fromExp, lit) + } + + case _ => exp + } + + private[sql] def falseIfNotNull(e: Expression): Expression = + And(IsNull(e), Literal(null, BooleanType)) Review comment: It's nicer to add a short comment, like "// Returns false if `e` is not null, otherwise returns null." ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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