feat(database): ✨ add custom preload handling for relations

* Introduced custom preloads to manage relations that may exceed PostgreSQL's identifier limit.
* Implemented checks for alias length to prevent truncation warnings.
* Enhanced the loading mechanism for nested relations using separate queries.

pkg/common/adapters/database/utils.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"strings"
 
+	"github.com/bitechdev/ResolveSpec/pkg/logger"
 	"github.com/uptrace/bun/dialect/mssqldialect"
 	"github.com/uptrace/bun/dialect/pgdialect"
 	"github.com/uptrace/bun/dialect/sqlitedialect"
@@ -13,6 +14,49 @@ import (
 	"gorm.io/gorm"
 )
 
+// PostgreSQL identifier length limit (63 bytes + null terminator = 64 bytes total)
+const postgresIdentifierLimit = 63
+
+// checkAliasLength checks if a preload relation path will generate aliases that exceed PostgreSQL's limit
+// Returns true if the alias is likely to be truncated
+func checkAliasLength(relation string) bool {
+	// Bun generates aliases like: parentalias__childalias__columnname
+	// For nested preloads, it uses the pattern: relation1__relation2__relation3__columnname
+	parts := strings.Split(relation, ".")
+	if len(parts) <= 1 {
+		return false // Single level relations are fine
+	}
+
+	// Calculate the actual alias prefix length that Bun will generate
+	// Bun uses double underscores (__) between each relation level
+	// and converts the relation names to lowercase with underscores
+	aliasPrefix := strings.ToLower(strings.Join(parts, "__"))
+	aliasPrefixLen := len(aliasPrefix)
+
+	// We need to add 2 more underscores for the column name separator plus column name length
+	// Column names in the error were things like "rid_mastertype_hubtype" (23 chars)
+	// To be safe, assume the longest column name could be around 35 chars
+	maxColumnNameLen := 35
+	estimatedMaxLen := aliasPrefixLen + 2 + maxColumnNameLen
+
+	// Check if this would exceed PostgreSQL's identifier limit
+	if estimatedMaxLen > postgresIdentifierLimit {
+		logger.Warn("Preload relation '%s' will generate aliases up to %d chars (prefix: %d + column: %d), exceeding PostgreSQL's %d char limit",
+			relation, estimatedMaxLen, aliasPrefixLen, maxColumnNameLen, postgresIdentifierLimit)
+		return true
+	}
+
+	// Also check if just the prefix is getting close (within 15 chars of limit)
+	// This gives room for column names
+	if aliasPrefixLen > (postgresIdentifierLimit - 15) {
+		logger.Warn("Preload relation '%s' has alias prefix of %d chars, which may cause truncation with longer column names (limit: %d)",
+			relation, aliasPrefixLen, postgresIdentifierLimit)
+		return true
+	}
+
+	return false
+}
+
 // parseTableName splits a table name that may contain schema into separate schema and table
 // For example: "public.users" -> ("public", "users")
 //