[3328] Removed use of PgSqlStatementBind

Unlike, MySQL, PostgreSQL does not return anything to the caller when
preparing an SQL statement, rather one uses its text name to execute it.
PgSqlStatementBind was an unecessary duplication of data already available
in tagged_statements.  This also resolved the unused member complaint from
cppcheck regarding TaggedStatement::index.

Also corrected two cppchecks in unit tests.

src/lib/dhcpsrv/pgsql_lease_mgr.cc

@@ -41,8 +41,6 @@ const size_t MAX_PARAMETERS_IN_QUERY = 13;
 struct TaggedStatement {
 
     /// Query index
-    /// @todo cppcheck flags index as unused
-    // cppcheck-suppress unusedStructMember
     PgSqlLeaseMgr::StatementIndex index;
 
     /// Number of parameters for a given query
@@ -901,9 +899,6 @@ PgSqlLeaseMgr::~PgSqlLeaseMgr() {
 
 void
 PgSqlLeaseMgr::prepareStatements() {
-    statements_.clear();
-    statements_.resize(NUM_STATEMENTS, PgSqlStatementBind());
-
     for(int i = 0; tagged_statements[i].text != NULL; ++ i) {
         // Prepare all statements queries with all known fields datatype
         PGresult* r = PQprepare(conn_, tagged_statements[i].name,
@@ -919,8 +914,6 @@ PgSqlLeaseMgr::prepareStatements() {
                       << PQerrorMessage(conn_));
         }
 
-        statements_[i].stmt_name = tagged_statements[i].name;
-        statements_[i].stmt_nbparams = tagged_statements[i].nbparams;
         PQclear(r);
     }
 }
@@ -980,9 +973,8 @@ PgSqlLeaseMgr::openDatabase() {
 bool
 PgSqlLeaseMgr::addLeaseCommon(StatementIndex stindex,
                               PsqlBindArray& bind_array) {
-//    std::cout << "addLeaseCommon: bind_array: " << bind_array.toText();
-    PGresult * r = PQexecPrepared(conn_, statements_[stindex].stmt_name,
-                                  statements_[stindex].stmt_nbparams,
+    PGresult * r = PQexecPrepared(conn_, tagged_statements[stindex].name,
+                                  tagged_statements[stindex].nbparams,
                                   &bind_array.values_[0],
                                   &bind_array.lengths_[0],
                                   &bind_array.formats_[0], 0);
@@ -1001,7 +993,7 @@ PgSqlLeaseMgr::addLeaseCommon(StatementIndex stindex,
         }
 
         isc_throw(DbOperationError, "unable to INSERT for " <<
-                  statements_[stindex].stmt_name << ", reason: " <<
+                  tagged_statements[stindex].name << ", reason: " <<
                   errorMsg);
     }
 
@@ -1037,10 +1029,10 @@ void PgSqlLeaseMgr::getLeaseCollection(StatementIndex stindex,
                                        LeaseCollection& result,
                                        bool single) const {
     LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE_DETAIL,
-              DHCPSRV_PGSQL_GET_ADDR4).arg(statements_[stindex].stmt_name);
+              DHCPSRV_PGSQL_GET_ADDR4).arg(tagged_statements[stindex].name);
 
-    PGresult* r = PQexecPrepared(conn_, statements_[stindex].stmt_name,
-                       statements_[stindex].stmt_nbparams,
+    PGresult* r = PQexecPrepared(conn_, tagged_statements[stindex].name,
+                       tagged_statements[stindex].nbparams,
                        &bind_array.values_[0],
                        &bind_array.lengths_[0],
                        &bind_array.formats_[0], 0);
@@ -1052,7 +1044,7 @@ void PgSqlLeaseMgr::getLeaseCollection(StatementIndex stindex,
         PQclear(r);
         isc_throw(MultipleRecords, "multiple records were found in the "
                       "database where only one was expected for query "
-                      << statements_[stindex].stmt_name);
+                      << tagged_statements[stindex].name);
     }
 
     for(int i = 0; i < rows; ++ i) {
@@ -1312,10 +1304,10 @@ PgSqlLeaseMgr::updateLeaseCommon(StatementIndex stindex,
                                  PsqlBindArray& bind_array,
                                  const LeasePtr& lease) {
     LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE_DETAIL,
-              DHCPSRV_PGSQL_ADD_ADDR4).arg(statements_[stindex].stmt_name);
+              DHCPSRV_PGSQL_ADD_ADDR4).arg(tagged_statements[stindex].name);
 
-    PGresult * r = PQexecPrepared(conn_, statements_[stindex].stmt_name,
-                                  statements_[stindex].stmt_nbparams,
+    PGresult * r = PQexecPrepared(conn_, tagged_statements[stindex].name,
+                                  tagged_statements[stindex].nbparams,
                                   &bind_array.values_[0],
                                   &bind_array.lengths_[0],
                                   &bind_array.formats_[0], 0);
@@ -1385,8 +1377,8 @@ PgSqlLeaseMgr::updateLease6(const Lease6Ptr& lease) {
 bool
 PgSqlLeaseMgr::deleteLeaseCommon(StatementIndex stindex,
                                  PsqlBindArray& bind_array) {
-    PGresult * r = PQexecPrepared(conn_, statements_[stindex].stmt_name,
-                                  statements_[stindex].stmt_nbparams,
+    PGresult * r = PQexecPrepared(conn_, tagged_statements[stindex].name,
+                                  tagged_statements[stindex].nbparams,
                                   &bind_array.values_[0],
                                   &bind_array.lengths_[0],
                                   &bind_array.formats_[0], 0);
@@ -1436,7 +1428,7 @@ PgSqlLeaseMgr::checkStatementError(PGresult* r, StatementIndex index) const {
         PQclear(r);
 
         isc_throw(DbOperationError, "Statement exec faild:" << " for: " <<
-                  statements_[index].stmt_name << ", reason: " <<
+                  tagged_statements[index].name << ", reason: " <<
                   PQerrorMessage(conn_));
     }
 }

src/lib/dhcpsrv/pgsql_lease_mgr.h

@@ -89,12 +89,6 @@ struct PsqlBindArray {
     std::string toText();
 };
 
-/// @brief Describes a single compiled statement
-struct PgSqlStatementBind {
-    const char* stmt_name; ///< Name of the compiled statement
-    int stmt_nbparams; ///< Number of statement parameters
-};
-
 // Forward definitions (needed for shared_ptr definitions)
 // See pgsql_lease_mgr.cc file for actual class definitions
 class PgSqlLease4Exchange;
@@ -597,9 +591,6 @@ private:
     boost::scoped_ptr<PgSqlLease4Exchange> exchange4_; ///< Exchange object
     boost::scoped_ptr<PgSqlLease6Exchange> exchange6_; ///< Exchange object
 
-    /// A vector of compiled SQL statements
-    std::vector<PgSqlStatementBind> statements_;
-
     /// PostgreSQL connection handle
     PGconn* conn_;
 };

src/lib/dhcpsrv/tests/pgsql_lease_mgr_unittest.cc

@@ -110,14 +110,13 @@ validConnectionString() {
 // tests will (should) fall over.
 void destroySchema() {
     // Open database
-    PGconn * conn = 0;
+    PGconn* conn = 0;
     conn = PQconnectdb("host = 'localhost' user = 'keatest'"
                        " password = 'keatest' dbname = 'keatest'");
 
-    PGresult * r;
     // Get rid of everything in it.
     for (int i = 0; destroy_statement[i] != NULL; ++i) {
-        r = PQexec(conn, destroy_statement[i]);
+        PGresult* r = PQexec(conn, destroy_statement[i]);
         PQclear(r);
     }
 
@@ -132,14 +131,13 @@ void destroySchema() {
 // will fall over.
 void createSchema() {
     // Open database
-    PGconn * conn = 0;
+    PGconn* conn = 0;
     conn = PQconnectdb("host = 'localhost' user = 'keatest'"
                        " password = 'keatest' dbname = 'keatest'");
 
-    PGresult * r;
     // Get rid of everything in it.
     for (int i = 0; create_statement[i] != NULL; ++i) {
-        r = PQexec(conn, create_statement[i]);
+        PGresult* r = PQexec(conn, create_statement[i]);
         PQclear(r);
     }