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copied!<h3>A Minor Diversion</h3> <p>You have some syntactic problems in what you show us:</p> <pre><code>sprintf(sqlQuery, "select distinct e.emp_id, e.join_date \ from employees e where e.emp_id in (?) and e.dob <= '%s')"); </code></pre> <p>That won't compile; you'd need a second backslash after <code>employees e</code>. I strong recommend avoiding backslash-newline in strings; use string concatenation instead.</p> <pre><code>sprintf(sqlQuery, "select distinct e.emp_id, e.join_date from employees e " "where e.emp_id in (?) and e.dob <= '%s')"); </code></pre> <p>Note that there is just white space (comments would count as white space too) between the two parts of the string; the C compiler concatenates such strings into a single string.</p> <p>Now the <code>sprintf()</code> call is syntactically correct at the C source level; it is still semantically incorrect because it contains <code>%s</code> and you've not provided a string for it to copy. You should presumably be using a placeholder <code>?</code> for the date since you pass it to the <code>$open</code> statement as a second parameter (but there isn't actually a placeholder for it).</p> <p>You would then be able to avoid an explicit prepare operation by writing:</p> <pre><code>$ DECLARE empDataCursor FOR SELECT DISTINCT e.emp_id, e.join_date FROM employees e WHERE e.emp_id IN ($empIds_) AND e.dob <= $dob_; </code></pre> <hr> <h3>The Crux</h3> <p>However, this isn't going to work for you, unfortunately. The crux of your problem is you are trying to pass a string as a list of values for the IN clause. It simply doesn't work like that. If you have one value, you need one placeholder (<code>?</code>); if you have two values, you need two placeholders, etc.</p> <p>So, we end up going back to a full prepared statement and substitute the empIds into the string:</p> <pre><code> int reqlen; reqlen = snprintf(sqlQuery, sizeof(sqlQuery), "SELECT DISTINCT e.emp_id, e.join_date" " FROM employees e WHERE e.emp_id IN (%s) AND e.dob <= '%s'", empIds_, dob_); if (reqlen >= sizeof(sqlQuery)) ...truncated SQL...larger sqlQuery needed... $ PREPARE empDataStmt FROM $sqlQuery; ...SQL error check... $ DECLARE empDataCursor FOR empDataStmt; ...SQL error check... $ OPEN empDataCursor; /* No USING clause! */ ...SQL error check... ...code as before... </code></pre>

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