Optimize oracle select statement parsing speed

apache · Sep 26, 2023 · 69b06e6 · 69b06e6
1 parent 898dcc9
commit 69b06e6
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Showing 2 changed files with 1 addition and 25 deletions.
diff --git a/parser/sql/dialect/oracle/src/main/antlr4/imports/oracle/DMLStatement.g4 b/parser/sql/dialect/oracle/src/main/antlr4/imports/oracle/DMLStatement.g4
@@ -136,11 +136,7 @@ select
     ;
 
 selectSubquery
-    : (queryBlock | selectCombineClause | parenthesisSelectSubquery) pivotClause? orderByClause? rowLimitingClause
-    ;
-
-selectCombineClause
-    : ((queryBlock | parenthesisSelectSubquery) orderByClause? rowLimitingClause) ((UNION ALL? | INTERSECT | MINUS) selectSubquery)+
+    : (queryBlock | parenthesisSelectSubquery) ((UNION ALL? | INTERSECT | MINUS) selectSubquery)? orderByClause?
     ;
 
 parenthesisSelectSubquery

diff --git a/...he/shardingsphere/sql/parser/oracle/visitor/statement/type/OracleDMLStatementVisitor.java b/...he/shardingsphere/sql/parser/oracle/visitor/statement/type/OracleDMLStatementVisitor.java
@@ -82,7 +82,6 @@
 import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.QueryTableExprContext;
 import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.ReferenceModelContext;
 import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.RollupCubeClauseContext;
-import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.SelectCombineClauseContext;
 import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.SelectContext;
 import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.SelectFromClauseContext;
 import org.apache.shardingsphere.sql.parser.autogen.OracleStatementParser.SelectJoinOptionContext;
@@ -530,8 +529,6 @@ public ASTNode visitSelectSubquery(final SelectSubqueryContext ctx) {
         OracleSelectStatement result;
         if (null != ctx.queryBlock()) {
             result = (OracleSelectStatement) visit(ctx.queryBlock());
-        } else if (null != ctx.selectCombineClause()) {
-            result = (OracleSelectStatement) visit(ctx.selectCombineClause());
         } else {
             result = (OracleSelectStatement) visit(ctx.parenthesisSelectSubquery());
         }
@@ -643,23 +640,6 @@ public ASTNode visitReferenceModel(final ReferenceModelContext ctx) {
         return new SubquerySegment(ctx.selectSubquery().start.getStartIndex(), ctx.selectSubquery().stop.getStopIndex(), subquery);
     }
 
-    @Override
-    public ASTNode visitSelectCombineClause(final SelectCombineClauseContext ctx) {
-        OracleSelectStatement result;
-        if (null != ctx.queryBlock()) {
-            result = (OracleSelectStatement) visit(ctx.queryBlock());
-        } else {
-            result = (OracleSelectStatement) visit(ctx.parenthesisSelectSubquery());
-        }
-        if (null != ctx.orderByClause()) {
-            result.setOrderBy((OrderBySegment) visit(ctx.orderByClause()));
-        }
-        for (SelectSubqueryContext each : ctx.selectSubquery()) {
-            visit(each);
-        }
-        return result;
-    }
-
     @Override
     public ASTNode visitParenthesisSelectSubquery(final ParenthesisSelectSubqueryContext ctx) {
         return visit(ctx.selectSubquery());