feat(db): Improve BuildCaseInsensitiveLike with lowercase

models/db/common.go

@@ -12,27 +12,30 @@ import (
 	"xorm.io/builder"
 )
 
-// BuildCaseInsensitiveLike returns a condition to check if the given value is like the given key case-insensitively.
+// BuildCaseInsensitiveLike returns a case-insensitive LIKE condition for the given key and value.
 // Handles especially SQLite correctly as UPPER there only transforms ASCII letters.
+// PostgreSQL uses ILIKE for pattern matching.
+// Other databases use LOWER(column) + LOWER(value) for case-insensitive matching.
 func BuildCaseInsensitiveLike(key, value string) builder.Cond {
 	if setting.Database.Type.IsSQLite3() {
 		return builder.Like{"UPPER(" + key + ")", util.ToUpperASCII(value)}
 	}
-	return builder.Like{"UPPER(" + key + ")", strings.ToUpper(value)}
+	if setting.Database.Type.IsPostgreSQL() {
+		return builder.Expr(key+" ILIKE ?", value)
+	}
+	return builder.Like{"LOWER(" + key + ")", strings.ToLower(value)}
 }
 
 // BuildCaseInsensitiveIn returns a condition to check if the given value is in the given values case-insensitively.
 // Handles especially SQLite correctly as UPPER there only transforms ASCII letters.
 func BuildCaseInsensitiveIn(key string, values []string) builder.Cond {
-	uppers := make([]string, 0, len(values))
+	uppers := make([]string, len(values))
+	transform := strings.ToUpper
 	if setting.Database.Type.IsSQLite3() {
-		for _, value := range values {
-			uppers = append(uppers, util.ToUpperASCII(value))
-		}
-	} else {
-		for _, value := range values {
-			uppers = append(uppers, strings.ToUpper(value))
-		}
+		transform = util.ToUpperASCII
+	}
+	for i, value := range values {
+		uppers[i] = transform(value)
 	}
 
 	return builder.In("UPPER("+key+")", uppers)

models/repo/user_repo.go

@@ -151,7 +151,7 @@ func GetRepoAssignees(ctx context.Context, repo *Repository) (_ []*user_model.Us
 func GetIssuePostersWithSearch(ctx context.Context, repo *Repository, isPull bool, search string, isShowFullName bool) ([]*user_model.User, error) {
 	users := make([]*user_model.User, 0, 30)
 	var prefixCond builder.Cond = builder.Like{"lower_name", strings.ToLower(search) + "%"}
-	if isShowFullName {
+	if search != "" && isShowFullName {
 		prefixCond = prefixCond.Or(db.BuildCaseInsensitiveLike("full_name", "%"+search+"%"))
 	}