fixed reading of null values for all backends

zussel · Jan 15, 2024 · 8256f2e · 8256f2e
1 parent 650e534
commit 8256f2e
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Showing 7 changed files with 84 additions and 15 deletions.
diff --git a/include/matador/db/postgresql/postgresql_getvalue.hpp b/include/matador/db/postgresql/postgresql_getvalue.hpp
@@ -14,6 +14,10 @@ namespace detail {
 template < typename T, typename std::enable_if<std::is_integral<T>::value && std::is_signed<T>::value && !std::is_same<T, char>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val = 0;
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   if (strlen(value) == 0) {
@@ -31,6 +35,10 @@ std::is_unsigned<T>::value &&
 >::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val = 0;
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   if (strlen(value) == 0) {
@@ -43,6 +51,10 @@ void get_value(PGresult *res, size_t row, size_t col, T &val)
 template < typename T, typename std::enable_if<std::is_same<T, bool>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val = false;
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   if (strlen(value) == 0) {
@@ -55,6 +67,10 @@ void get_value(PGresult *res, size_t row, size_t col, T &val)
 template < typename T, typename std::enable_if<std::is_same<T, char>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val = 0;
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   if (strlen(value) == 0) {
@@ -67,6 +83,10 @@ void get_value(PGresult *res, size_t row, size_t col, T &val)
 template < typename T, typename std::enable_if<std::is_floating_point<T>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val = 0;
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   if (strlen(value) == 0) {
@@ -79,24 +99,41 @@ void get_value(PGresult *res, size_t row, size_t col, T &val)
 template < typename T, typename std::enable_if<std::is_same<T, std::string>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val.clear();
+    return;
+  }
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    return;
+  }
   val = PQgetvalue(res, (int)row, (int)col);
 }
 
 template < typename T, typename std::enable_if<std::is_same<T, std::string>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val, size_t)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    val.clear();
+    return;
+  }
   val = PQgetvalue(res, (int)row, (int)col);
 }
 
 template < typename T, typename std::enable_if<std::is_same<T, matador::time>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    return;
+  }
   val = matador::time::parse(PQgetvalue(res, (int)row, (int)col), "%Y-%m-%d %T.%f");
 }
 
 template < typename T, typename std::enable_if<std::is_same<T, matador::date>::value>::type* = nullptr>
 void get_value(PGresult *res, size_t row, size_t col, T &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    return;
+  }
   val.set(PQgetvalue(res, (int)row, (int)col), date_format::ISO8601);
 }
 

diff --git a/src/db/mssql/mssql_result.cpp b/src/db/mssql/mssql_result.cpp
@@ -172,6 +172,8 @@ void mssql_result::read_column(const char *, size_type index, std::string &val)
   if (SQL_SUCCEEDED(ret)) {
     if (info > 0) {
       val.assign(buf, info);
+    } else {
+      val.clear();
     }
   } else {
     throw_database_error(ret, SQL_HANDLE_STMT, stmt_, "mssql");
@@ -189,6 +191,8 @@ void mssql_result::read_column(const char *, size_type index, std::string &val,
   if (SQL_SUCCEEDED(ret)) {
     if (info > 0) {
       val.assign(buf.data(), info);
+    } else {
+      val.clear();
     }
   } else {
     throw_database_error(ret, SQL_HANDLE_STMT, stmt_, "mssql");
@@ -225,7 +229,9 @@ void mssql_result::read_column(char const *, size_type index, date &x)
   SQLLEN info = 0;
   SQLRETURN ret = SQLGetData(stmt_, static_cast<SQLUSMALLINT>(index), SQL_C_TYPE_DATE, &ds, 0, &info);
   if (SQL_SUCCEEDED(ret)) {
-    x.set(ds.day, ds.month, ds.year);
+    if (info != SQL_NULL_DATA) {
+      x.set(ds.day, ds.month, ds.year);
+    }
   } else {
     throw_database_error(ret, SQL_HANDLE_STMT, stmt_, "mssql");
   }
@@ -238,7 +244,9 @@ void mssql_result::read_column(char const *, size_type index, time &x)
   SQLLEN info = 0;
   SQLRETURN ret = SQLGetData(stmt_, static_cast<SQLUSMALLINT>(index), SQL_C_TYPE_TIMESTAMP, &ts, 0, &info);
   if (SQL_SUCCEEDED(ret)) {
-    x.set(ts.year, ts.month, ts.day, ts.hour, ts.minute, ts.second, ts.fraction / 1000 / 1000);
+    if (info != SQL_NULL_DATA) {
+      x.set(ts.year, ts.month, ts.day, ts.hour, ts.minute, ts.second, ts.fraction / 1000 / 1000);
+    }
   } else {
     throw_database_error(ret, SQL_HANDLE_STMT, stmt_, "mssql");
   }

diff --git a/src/db/mysql/mysql_result.cpp b/src/db/mysql/mysql_result.cpp
@@ -245,6 +245,7 @@ void mysql_result::read_value(const char */*id*/, size_type index, std::string &
 {
   char *val = row_[index];
   if (val == nullptr) {
+    value.clear();
     return;
   }
   value.assign(val);
@@ -254,6 +255,7 @@ void mysql_result::read_value(const char */*id*/, size_type index, std::string &
 {
   char *val = row_[index];
   if (val == nullptr) {
+    value.clear();
     return;
   }
   value.assign(val);

diff --git a/src/db/postgresql/postgresql_getvalue.cpp b/src/db/postgresql/postgresql_getvalue.cpp
@@ -5,6 +5,9 @@ namespace detail {
 
 void get_value(PGresult *res, size_t row, size_t col, char *val, size_t s)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   size_t len = strlen(value);
@@ -26,6 +29,9 @@ void get_value(PGresult *res, size_t row, size_t col, char *val, size_t s)
 
 void get_value(PGresult *res, size_t row, size_t col, unsigned char &val)
 {
+  if (PQgetisnull(res, (int)row, (int)col) == 1) {
+    return;
+  }
   auto value = PQgetvalue(res, (int)row, (int)col);
 
   if (strlen(value) == 0) {

diff --git a/src/db/sqlite/sqlite_prepared_result.cpp b/src/db/sqlite/sqlite_prepared_result.cpp
@@ -119,7 +119,9 @@ void sqlite_prepared_result::read_value(const char */*id*/, size_type index, std
 {
   auto s = (size_t)sqlite3_column_bytes(stmt_, index);
   auto *text = (const char*)sqlite3_column_text(stmt_, index);
-  x.assign(text, s);
+  if (s > 0) {
+    x.assign(text, s);
+  }
 }
 
 void sqlite_prepared_result::read_value(const char */*id*/, size_type index, std::string &x, size_t /*size*/)
@@ -153,16 +155,22 @@ void sqlite_prepared_result::read_value(const char */*id*/, size_type index, cha
 
 void sqlite_prepared_result::read_value(const char *id, size_type index, matador::date &x)
 {
-  std::string val;
-  read_value(id, index, val);
-  x = matador::date::parse(val, date_format::ISO8601);
+  auto is_null = sqlite3_column_type(stmt_, index) == SQLITE_NULL;
+  auto s = (size_t)sqlite3_column_bytes(stmt_, index);
+  if (!is_null && s > 0) {
+    const auto *text = reinterpret_cast<const char *>( sqlite3_column_text(stmt_, index));
+    x = matador::date::parse(text, date_format::ISO8601);
+  }
 }
 
 void sqlite_prepared_result::read_value(const char *id, size_type index, matador::time &x)
 {
-  std::string val;
-  read_value(id, index, val);
-  x = matador::time::parse(val, "%Y-%m-%dT%T.%f");
+  auto is_null = sqlite3_column_type(stmt_, index) == SQLITE_NULL;
+  auto s = (size_t)sqlite3_column_bytes(stmt_, index);
+  if (!is_null && s > 0) {
+    const auto *text = reinterpret_cast<const char *>( sqlite3_column_text(stmt_, index));
+    x = matador::time::parse(text, "%Y-%m-%dT%T.%f");
+  }
 }
 
 bool sqlite_prepared_result::prepare_fetch()

diff --git a/src/db/sqlite/sqlite_result.cpp b/src/db/sqlite/sqlite_result.cpp
@@ -261,13 +261,17 @@ void sqlite_result::read_value(const char */*id*/, size_type index, std::string
 void sqlite_result::read_value(const char */*id*/, size_type index, matador::date &x)
 {
   t_row::value_type val = result_[row_index_][index];
-  x.set(val, date_format::ISO8601);
+  if (strlen(val) > 0) {
+    x.set(val, date_format::ISO8601);
+  }
 }
 
 void sqlite_result::read_value(const char */*id*/, size_type index, matador::time &x)
 {
   t_row::value_type val = result_[row_index_][index];
-  x = matador::time::parse(val, "%Y-%m-%dT%T.%f");
+  if (strlen(val) > 0) {
+    x = matador::time::parse(val, "%Y-%m-%dT%T.%f");
+  }
 }
 
 bool sqlite_result::prepare_fetch()

diff --git a/test/sql/QueryTestUnit.cpp b/test/sql/QueryTestUnit.cpp
@@ -624,19 +624,23 @@ void QueryTestUnit::test_null_column()
   q.create("person", {
     make_pk_column<long>("id"),
     make_column<std::string>("name", 63),
-    make_column<unsigned>("age")
+    make_column<matador::date>("birthday")
   });
 
   q.execute(connection_);
 
-  q.insert("person", {"id", "age"}).values({1, 47}).execute(connection_);
+  q.insert("person", {"id", "name"}).values({1, "george"}).execute(connection_);
+  q.insert("person", {"id", "birthday"}).values({2, date{27, 11, 1954}}).execute(connection_);
 
-  auto res = q.select({"id", "name", "age"}).from("person").execute(connection_);
+  auto res = q.select({"id", "name", "birthday"}).from("person").execute(connection_);
 
+  std::vector<std::string> expected_names{"george", ""};
+  size_t index{0};
   for (const auto& r : res) {
     auto name = r->at<std::string>("name");
-    UNIT_EXPECT_TRUE(name.empty());
+    UNIT_EXPECT_EQUAL(name, expected_names[index++]);
   }
+
   q.drop("person").execute(connection_);
 }