From 8f2e7618286a8d1f39b875f48177c2bc8d09d930 Mon Sep 17 00:00:00 2001
From: Ansgar Becker <anse@heidisql.com>
Date: Fri, 28 Apr 2023 14:44:54 +0200
Subject: [PATCH] Issue #1800: attempt to distinguish text values from function
 expressions in a column's default value, for MySQL 8.0.13+ which seems to
 allow just all functions as default value.

---
 source/dbconnection.pas | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/source/dbconnection.pas b/source/dbconnection.pas
index 0dfd3cec..7818bd67 100644
--- a/source/dbconnection.pas
+++ b/source/dbconnection.pas
@@ -5589,11 +5589,21 @@ begin
     // Inexact fallback detection, wrong if MariaDB allows "0+1" as expression at some point
     Result := Result or Value.IsEmpty or IsInt(Value[1]);
   end else if FParameters.IsAnyMySQL then begin
-    // Only MySQL case with expression in default value is as follows:
-    if (Tp.Category = dtcTemporal) and Value.StartsWith('CURRENT_TIMESTAMP', True) then begin
-      Result := False;
-    end else begin
-      Result := True;
+    if ServerVersionInt <= 80013 then begin
+      // Only MySQL case with expression in default value is as follows:
+      if (Tp.Category = dtcTemporal) and Value.StartsWith('CURRENT_TIMESTAMP', True) then begin
+        Result := False;
+      end else begin
+        Result := True;
+      end;
+    end
+    else begin
+      // https://dev.mysql.com/doc/refman/8.0/en/data-type-defaults.html#data-type-defaults-explicit
+      // MySQL 8.0.13+ expect expressions to be wrapped in (..) when you create a table.
+      // But checking if first char is an opening parenthesis does not work here, as we get the expression
+      // from IS.COLUMNS, not from SHOW CREATE TABLE. So here's a workaround for distinguishing text
+      // from an expression:
+      Result := not Value.Contains('(');
     end;
   end else begin
     // MS SQL, PG and SQLite: