From 35e94c8abd3767eb44620cdf7246ba04f9d9252c Mon Sep 17 00:00:00 2001
From: tobi <31960611+tsmethurst@users.noreply.github.com>
Date: Sun, 9 Mar 2025 16:44:12 +0100
Subject: [PATCH] [bugfix] Fix `length for type varchar must be at least 1` on
 Postgres (#3885)

---
 internal/db/bundb/migrations/util.go | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/internal/db/bundb/migrations/util.go b/internal/db/bundb/migrations/util.go
index 6ffcdd09d..b8a60417d 100644
--- a/internal/db/bundb/migrations/util.go
+++ b/internal/db/bundb/migrations/util.go
@@ -253,9 +253,14 @@ func getBunColumnDef(db bun.IDB, rtype reflect.Type, fieldName string) (string,
 		} else {
 			buf = append(buf, sqltype.VarChar...)
 		}
-		buf = append(buf, "("...)
-		buf = strconv.AppendInt(buf, int64(d.DefaultVarcharLen()), 10)
-		buf = append(buf, ")"...)
+
+		// Only specify varchar length for dialects
+		// where specifying VARCHAR length is mandatory.
+		if dvl := d.DefaultVarcharLen(); dvl != 0 {
+			buf = append(buf, "("...)
+			buf = strconv.AppendInt(buf, int64(dvl), 10)
+			buf = append(buf, ")"...)
+		}
 	}
 
 	// Append not null definition if field requires.