[fix][dingo-calcite] Add substr function; support charLiteral alias

Author: guojn1

dingo-calcite/src/main/java/io/dingodb/calcite/DingoParser.java

@@ -72,7 +72,6 @@
 import io.dingodb.calcite.program.DecorrelateProgram;
 import io.dingodb.calcite.rel.DingoCost;
 import io.dingodb.calcite.rel.LogicalExportData;
-import io.dingodb.calcite.rel.LogicalForUpdate;
 import io.dingodb.calcite.rel.logical.LogicalDingoRoot;
 import io.dingodb.calcite.rule.DingoRules;
 import io.dingodb.calcite.runtime.DingoResource;
@@ -97,7 +96,6 @@
 import org.apache.calcite.plan.ConventionTraitDef;
 import org.apache.calcite.plan.RelOptCluster;
 import org.apache.calcite.plan.RelOptRule;
-import org.apache.calcite.plan.RelOptTable;
 import org.apache.calcite.plan.RelTraitSet;
 import org.apache.calcite.plan.ViewExpanders;
 import org.apache.calcite.plan.volcano.AbstractConverter;
@@ -198,6 +196,11 @@ public boolean isOffsetLimitAllowed() {
             public boolean isInsertSubsetColumnsAllowed() {
                 return false;
             }
+
+            @Override
+            public boolean allowCharLiteralAlias() {
+                return true;
+            }
         });
 
     @Getter
@@ -213,7 +216,6 @@ public boolean isInsertSubsetColumnsAllowed() {
 
     public DingoParser(final @NonNull DingoParserContext context) {
         this.context = context;
-
         // Create Planner.
         planner = new VolcanoPlanner(DingoCost.FACTORY, context);
         // Set to `true` to use `TopDownRuleDriver`, or `IterativeRuleDriver` is used.

dingo-calcite/src/main/java/io/dingodb/calcite/fun/DingoOperatorTable.java

@@ -111,6 +111,7 @@ private void init() {
         funMap.put("NOW", SqlStdOperatorTable.CURRENT_TIMESTAMP);
         funMap.put("CURDATE", SqlStdOperatorTable.CURRENT_DATE);
         funMap.put("CURTIME", SqlStdOperatorTable.CURRENT_TIME);
+        funMap.put("SUBSTR", SqlStdOperatorTable.SUBSTRING);
 
         // number
         registerFunction(

dingo-exec/src/main/java/io/dingodb/exec/fun/DingoFunFactory.java

@@ -47,6 +47,7 @@ private DingoFunFactory() {
         super(ExprConfig.ADVANCED);
         registerBinaryFun(SUBSTRING, Exprs.MID2);
         registerTertiaryFun(SUBSTRING, Exprs.MID3);
+        registerTertiaryFun("SUBSTR", Exprs.MID3);
         registerBinaryFun(PowFunFactory.NAME, PowFunFactory.INSTANCE);
         registerNullaryFun(ThrowFun.NAME, ThrowFun.INSTANCE);