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copied!<p>You need to pass the array where you want to store the data in as the 1st argument to the callback as shown in sqlite3 <a href="http://sqlite.org/c3ref/exec.html">docs</a></p> <pre><code>int sqlite3_exec( sqlite3*, /* An open database */ const char *sql, /* SQL to be evaluated */ int (*callback)(void*,int,char**,char**), /* Callback function */ void *, /* 1st argument to callback */ char **errmsg /* Error msg written here */ ); </code></pre> <p>Here's a contrived example based on your code with some tidy up:</p> <pre><code>#include <vector> #include <string> #include <iostream> #include "sqlite3.h" using namespace std; sqlite3* db; using Record = std::vector<std::string>; using Records = std::vector<Record>; int select_callback(void *p_data, int num_fields, char **p_fields, char **p_col_names) { Records* records = static_cast<Records*>(p_data); try { records->emplace_back(p_fields, p_fields + num_fields); } catch (...) { // abort select on failure, don't let exception propogate thru sqlite3 call-stack return 1; } return 0; } Records select_stmt(const char* stmt) { Records records; char *errmsg; int ret = sqlite3_exec(db, stmt, select_callback, &records, &errmsg); if (ret != SQLITE_OK) { std::cerr << "Error in select statement " << stmt << "[" << errmsg << "]\n"; } else { std::cerr << records.size() << " records returned.\n"; } return records; } void sql_stmt(const char* stmt) { char *errmsg; int ret = sqlite3_exec(db, stmt, 0, 0, &errmsg); if (ret != SQLITE_OK) { std::cerr << "Error in select statement " << stmt << "[" << errmsg << "]\n"; } } int main() { if (sqlite3_open("test.db", &db) != SQLITE_OK) { std::cerr << "Could not open database.\n"; return 1; } Records records = select_stmt("SELECT * FROM test"); sqlite3_close(db); for (auto& record : records) { // do something with your records } return 0; } </code></pre> <p>Your question is tag c++, so I've removed your use of the standard c api calls in favour of standard c++.</p>

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