Don't wrap read-only queries in a transaction

There is no risk of getting an inconsistent result here: if the ID
returned by queryValidPathId() is deleted from the database
concurrently, subsequent queries involving that ID will simply fail
(since IDs are never reused).

1 files changed, 0 insertions, 6 deletions

diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 7f7f70bb8857..f88af10f7ae9 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -929,8 +929,6 @@ PathSet LocalStore::queryValidDerivers(const Path & path)
 
 PathSet LocalStore::queryDerivationOutputs(const Path & path)
 {
-    SQLiteTxn txn(db);
-
     SQLiteStmtUse use(stmtQueryDerivationOutputs);
     stmtQueryDerivationOutputs.bind(queryValidPathId(path));
 
@@ -951,8 +949,6 @@ PathSet LocalStore::queryDerivationOutputs(const Path & path)
 
 StringSet LocalStore::queryDerivationOutputNames(const Path & path)
 {
-    SQLiteTxn txn(db);
-
     SQLiteStmtUse use(stmtQueryDerivationOutputs);
     stmtQueryDerivationOutputs.bind(queryValidPathId(path));
 
@@ -975,8 +971,6 @@ Path LocalStore::queryPathFromHashPart(const string & hashPart)
 {
     if (hashPart.size() != 32) throw Error("invalid hash part");
 
-    SQLiteTxn txn(db);
-
     Path prefix = settings.nixStore + "/" + hashPart;
 
     SQLiteStmtUse use(stmtQueryPathFromHashPart);