Use prepared statements for bulk selects

1 files changed, 29 insertions, 0 deletions

diff --git a/libpqpp/pq-prepared.cpp b/libpqpp/pq-prepared.cpp
new file mode 100644
index 0000000..4cd4540
--- /dev/null
+++ b/libpqpp/pq-prepared.cpp
@@ -0,0 +1,29 @@
+#include "pq-prepared.h"
+#include "pq-connection.h"
+
+PQ::PreparedStatement::PreparedStatement(Connection * c, const std::string & sql, unsigned int no) :
+	DB::Command(sql),
+	Command(c, sql, no),
+	pstmt(nullptr)
+{
+}
+
+const char *
+PQ::PreparedStatement::prepare() const
+{
+	if (pstmt) {
+		return pstmt;
+	}
+	auto hash(std::hash<std::string>()(sql));
+	auto i = c->preparedStatements.find(hash);
+	if (i != c->preparedStatements.end()) {
+		return (pstmt = i->second.c_str());
+	}
+	std::string psql;
+	psql.reserve(sql.length() + 20);
+	prepareSql(psql, sql);
+	c->checkResultFree(PQprepare(
+				c->conn, stmntName.c_str(), psql.c_str(), values.size(), NULL), PGRES_COMMAND_OK);
+	return (pstmt = c->preparedStatements.insert({hash, stmntName}).first->second.c_str());
+}
+