[Enhancement] Control implicit cast optimization by cbo_eq_type (Star…

…Rocks#40619) Signed-off-by: Seaven <seaven_7@qq.com>
Seaven · Feb 27, 2024 · 3594985 · 3594985
1 parent 41f0d7d
commit 3594985
Show file tree

Hide file tree

Showing 4 changed files with 64 additions and 24 deletions.
diff --git a/fe/fe-core/src/main/java/com/starrocks/qe/SessionVariable.java b/fe/fe-core/src/main/java/com/starrocks/qe/SessionVariable.java
@@ -1081,6 +1081,10 @@ public String getCboEqBaseType() {
         return cboEqBaseType;
     }
 
+    public void setCboEqBaseType(String cboEqBaseType) {
+        this.cboEqBaseType = cboEqBaseType;
+    }
+
     @VarAttr(name = FOLLOWER_QUERY_FORWARD_MODE, flag = VariableMgr.INVISIBLE | VariableMgr.DISABLE_FORWARD_TO_LEADER)
     private String followerForwardMode = "";
 

diff --git a/fe/fe-core/src/main/java/com/starrocks/sql/optimizer/rewrite/scalar/ImplicitCastRule.java b/fe/fe-core/src/main/java/com/starrocks/sql/optimizer/rewrite/scalar/ImplicitCastRule.java
@@ -9,6 +9,7 @@
 import com.starrocks.catalog.Function;
 import com.starrocks.catalog.FunctionSet;
 import com.starrocks.catalog.Type;
+import com.starrocks.qe.ConnectContext;
 import com.starrocks.sql.common.TypeManager;
 import com.starrocks.sql.optimizer.Utils;
 import com.starrocks.sql.optimizer.operator.scalar.BetweenPredicateOperator;
@@ -133,27 +134,12 @@ public ScalarOperator visitBinaryPredicate(BinaryPredicateOperator predicate,
         }
 
         // we will try cast const operator to variable operator
-        if (rightChild.isVariable() && leftChild.isConstantRef()) {
-            Optional<ScalarOperator> op = Utils.tryCastConstant(leftChild, type2);
-            if (op.isPresent()) {
-                predicate.getChildren().set(0, op.get());
-                return predicate;
-            } else if (rightChild.getType().isDateType() && !leftChild.getType().isDateType() &&
-                    Type.canCastTo(leftChild.getType(), rightChild.getType())) {
-                // For like MySQL, convert to date type as much as possible
-                addCastChild(rightChild.getType(), predicate, 0);
-                return predicate;
-            }
-        } else if (leftChild.isVariable() && rightChild.isConstantRef()) {
-            Optional<ScalarOperator> op = Utils.tryCastConstant(rightChild, type1);
-            if (op.isPresent()) {
-                predicate.getChildren().set(1, op.get());
-                return predicate;
-            } else if (leftChild.getType().isDateType() && !rightChild.getType().isDateType() &&
-                    Type.canCastTo(rightChild.getType(), leftChild.getType())) {
-                // For like MySQL, convert to date type as much as possible
-                addCastChild(leftChild.getType(), predicate, 1);
-                return predicate;
+        if (rightChild.isVariable() != leftChild.isVariable()) {
+            int constant = leftChild.isVariable() ? 1 : 0;
+            int variable = 1 - constant;
+            Optional<BinaryPredicateOperator> optional = optimizeConstantAndVariable(predicate, constant, variable);
+            if (optional.isPresent()) {
+                return optional.get();
             }
         }
 
@@ -169,6 +155,35 @@ public ScalarOperator visitBinaryPredicate(BinaryPredicateOperator predicate,
         return predicate;
     }
 
+    private Optional<BinaryPredicateOperator> optimizeConstantAndVariable(BinaryPredicateOperator predicate,
+                                                                          int constantIndex, int variableIndex) {
+        ScalarOperator constant = predicate.getChild(constantIndex);
+        ScalarOperator variable = predicate.getChild(variableIndex);
+        Type typeConstant = constant.getType();
+        Type typeVariable = variable.getType();
+
+        if (typeVariable.isStringType() && typeConstant.isExactNumericType()) {
+            if (ConnectContext.get() == null || "decimal".equalsIgnoreCase(
+                    ConnectContext.get().getSessionVariable().getCboEqBaseType())) {
+                // don't optimize when cbo_eq_base_type is decimal
+                return Optional.empty();
+            }
+        }
+
+        Optional<ScalarOperator> op = Utils.tryCastConstant(constant, variable.getType());
+        if (op.isPresent()) {
+            predicate.getChildren().set(constantIndex, op.get());
+            return Optional.of(predicate);
+        } else if (variable.getType().isDateType() && !constant.getType().isDateType() &&
+                Type.canCastTo(constant.getType(), variable.getType())) {
+            // For like MySQL, convert to date type as much as possible
+            addCastChild(variable.getType(), predicate, constantIndex);
+            return Optional.of(predicate);
+        }
+
+        return Optional.empty();
+    }
+
     @Override
     public ScalarOperator visitCompoundPredicate(CompoundPredicateOperator predicate,
                                                  ScalarOperatorRewriteContext context) {

diff --git a/fe/fe-core/src/test/java/com/starrocks/sql/optimizer/rewrite/ScalarOperatorRewriterTest.java b/fe/fe-core/src/test/java/com/starrocks/sql/optimizer/rewrite/ScalarOperatorRewriterTest.java
@@ -82,10 +82,10 @@ public void testRewrite2() {
         assertEquals(root, result);
         assertEquals(OperatorType.BINARY, result.getChild(0).getOpType());
         assertEquals(OperatorType.VARIABLE, result.getChild(0).getChild(0).getOpType());
-        assertEquals(OperatorType.CONSTANT, result.getChild(0).getChild(1).getOpType());
+        assertEquals(OperatorType.CALL, result.getChild(0).getChild(1).getOpType());
 
-        assertEquals(Type.VARCHAR, result.getChild(0).getChild(0).getType());
-        assertEquals(Type.VARCHAR, result.getChild(0).getChild(1).getType());
+        assertEquals(Type.VARCHAR.getPrimitiveType(), result.getChild(0).getChild(0).getType().getPrimitiveType());
+        assertEquals(Type.VARCHAR.getPrimitiveType(), result.getChild(0).getChild(1).getType().getPrimitiveType());
 
         assertEquals(OperatorType.COMPOUND, result.getChild(1).getOpType());
         assertEquals(OperatorType.BINARY, result.getChild(1).getChild(0).getOpType());

diff --git a/fe/fe-core/src/test/java/com/starrocks/sql/plan/ExpressionTest.java b/fe/fe-core/src/test/java/com/starrocks/sql/plan/ExpressionTest.java
@@ -1403,4 +1403,25 @@ public void testDecimalV2Cast1() throws Exception {
         plan = getVerboseExplain(sql);
         assertContains(plan, "3 <-> length[(cast(2480.0 as VARCHAR)); args: VARCHAR; result: INT;");
     }
+
+    @Test
+    public void testCastStringDouble() throws Exception {
+        try {
+            connectContext.getSessionVariable().setCboEqBaseType("VARCHAR");
+            String sql = "select t1a = 1 from test_all_type";
+            String plan = getVerboseExplain(sql);
+            assertContains(plan, "11 <-> [1: t1a, VARCHAR, true] = '1'");
+        } finally {
+            connectContext.getSessionVariable().setCboEqBaseType("VARCHAR");
+        }
+
+        try {
+            connectContext.getSessionVariable().setCboEqBaseType("DECIMAL");
+            String sql = "select t1a = 1 from test_all_type";
+            String plan = getVerboseExplain(sql);
+            assertContains(plan, "cast([1: t1a, VARCHAR, true] as DECIMAL128(38,9)) = 1");
+        } finally {
+            connectContext.getSessionVariable().setCboEqBaseType("VARCHAR");
+        }
+    }
 }