improved mysql 8.16 support, sql parser support check not enforced option, fix #4082

src/main/java/com/alibaba/druid/sql/ast/statement/SQLCheck.java

@@ -23,6 +23,7 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLCheck extends SQLConstraintImpl implements SQLTableElement, SQLTableConstraint, SQLReplaceable {
 
     private SQLExpr expr;
+    private Boolean enforced;
 
     public SQLCheck(){
 
@@ -63,6 +64,8 @@ public class SQLCheck extends SQLConstraintImpl implements SQLTableElement, SQLT
         if (expr != null) {
             expr = expr.clone();
         }
+
+        x.enforced = enforced;
     }
 
     public SQLCheck clone() {
@@ -89,4 +92,12 @@ public class SQLCheck extends SQLConstraintImpl implements SQLTableElement, SQLT
         }
         return false;
     }
+
+    public Boolean getEnforced() {
+        return enforced;
+    }
+
+    public void setEnforced(Boolean enforced) {
+        this.enforced = enforced;
+    }
 }

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlCreateTableParser.java

@@ -1549,6 +1549,22 @@ public class MySqlCreateTableParser extends SQLCreateTableParser {
             SQLExpr expr = this.exprParser.expr();
             check.setExpr(expr);
             constraint = check;
+
+            if (lexer.token() == Token.HINT) {
+                String hintText = lexer.stringVal();
+                if (hintText != null) {
+                    hintText = hintText.trim();
+                }
+
+                if (hintText.startsWith("!")) {
+                    if (hintText.endsWith("NOT ENFORCED")) {
+                        check.setEnforced(false);
+                    } else if (hintText.endsWith(" ENFORCED")) {
+                        check.setEnforced(true);
+                    }
+                    lexer.nextToken();
+                }
+            }
         }
 
         if (constraint != null) {

src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java

@@ -5273,6 +5273,16 @@ public class SQLASTOutputVisitor extends SQLASTVisitorAdapter implements Paramet
         x.getExpr().accept(this);
         this.indentCount--;
         print(')');
+
+        Boolean enforced = x.getEnforced();
+        if (enforced != null) {
+            if (enforced.booleanValue()) {
+                print0(ucase ? " ENFORCED" : " enforced");
+            } else {
+                print0(ucase ? " NOT ENFORCED" : " not enforced");
+            }
+        }
+
         return false;
     }
 

src/test/java/com/alibaba/druid/bvt/sql/mysql/visitor/MySqlResourceTest.java

@@ -58,6 +58,9 @@ public class MySqlResourceTest extends TestCase {
     public void test_16() throws Exception {
         exec_test("bvt/parser/mysql-16.txt");
     }
+    public void test_17() throws Exception {
+        exec_test("bvt/parser/mysql-17.txt");
+    }
 
     public void exec_test(String resource) throws Exception {
 //        System.out.println(resource);

src/test/resources/bvt/parser/mysql-17.txt

@@ -0,0 +1,23 @@
+CREATE TABLE `t12` (
+  `c1` int DEFAULT NULL,
+  `c2` int DEFAULT NULL,
+  `c3` int DEFAULT NULL,
+  CONSTRAINT `c12_positive` CHECK ((`c2` > 0)) /*!80016 NOT ENFORCED */,
+  CONSTRAINT `c21_nonzero` CHECK ((`c1` <> 0)),
+  CONSTRAINT `t12_chk_1` CHECK ((`c1` <> `c2`)),
+  CONSTRAINT `t12_chk_2` CHECK ((`c1` > 10)),
+  CONSTRAINT `t12_chk_3` CHECK ((`c3` < 100)),
+  CONSTRAINT `t12_chk_4` CHECK ((`c1` > `c3`))
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
+---------------------------
+CREATE TABLE `t12` (
+	`c1` int DEFAULT NULL,
+	`c2` int DEFAULT NULL,
+	`c3` int DEFAULT NULL,
+	CONSTRAINT `c12_positive` CHECK (`c2` > 0) NOT ENFORCED,
+	CONSTRAINT `c21_nonzero` CHECK (`c1` <> 0),
+	CONSTRAINT `t12_chk_1` CHECK (`c1` <> `c2`),
+	CONSTRAINT `t12_chk_2` CHECK (`c1` > 10),
+	CONSTRAINT `t12_chk_3` CHECK (`c3` < 100),
+	CONSTRAINT `t12_chk_4` CHECK (`c1` > `c3`)
+) ENGINE = InnoDB CHARSET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci