Manipulate command query string to return 1 COUNT clause?

Question

I've created a winforms application that allows users to set their criteria, query ibm 400 system, view results, then mail merge selected results. As an extra feature, I'm trying to set a label that will tell users upon criteria selection (searching via code, not them clicking Search) how many records have been printed out of total results for given criteria.

Example: 30 of 35 printed.

This means 30 documents have been marked in tracking table as printed out of 35 total.

Currently I am working on the total record count of that string, not the "how many printed" portion. So currently, my code is setting the label as "# of" + RecCount + " printed.".

I'm running into some issues though. Users have their choice of 3 data sources: System1, System2, and BOTH.

The following details my queries and the results:

CRITERIA: 20121209, System1, ALL RECORDS, OLD ADDR

QUERY: SELECT COUNT(*) AS RecCount FROM Library2.Table1 a, Library2.Table2 b WHERE a.memno = b.memno and b.groupid = 'N2' and b.type = 'B' and b.datec = 20131209 AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip)

RETURNED CNT: 24

CRITERIA: 20121209, System2, ALL RECORDS, OLD ADDR

QUERY: SELECT COUNT(*) AS RecCount FROM psrslib.pai000pf a, psrslib.pch010pf b WHERE a.memno = b.memno and b.groupid = 'PAI0002' and b.type = 'B' and b.datec = 20131209 AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip)

RETURNED CNT: 14

These 2 above seem to be functioning appropriately. But when I come to the BOTH datasource:

CRITERIA: 20121209, BOTH, ALL RECORDS, OLD ADDR

QUERY: SELECT COUNT() AS RecCount FROM psrslib.pai000pf a, psrslib.pch010pf b WHERE a.memno = b.memno and b.groupid = 'PAI0002' and b.type = 'B' and b.datec = 20131209 AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip) UNION SELECT COUNT() AS RecCount FROM ntrslib.nai000pf a, ntrslib.nch010pf b WHERE a.memno = b.memno and b.groupid = 'NAI0002' and b.type = 'B' and b.datec = 20131209 AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip)

RETURNED CNT: 24 -- // This should be 38

Upon inspecting my code and using server explorer I found the following:

My original Search Query before string manipulation to only receive the Count:

SELECT a.memno, 
a.name, 
a.addr1, 
a.addr2, 
a.city, 
a.state, 
a.zip, 
a.sex, 
a.lname, 
a.ssan, 
b.addr1 as old_addr1, 
b.addr2 as old_addr2, 
b.city as old_city, 
b.state as old_state, 
b.zip as old_zip, 
b.timec 

FROM Library1.Table1 a, Libary1.Table2 b 
WHERE a.memno = b.memno and 
b.groupid = 'P2' and 
b.type = 'B' and 
b.datec = 20131209 
AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip) 

UNION SELECT a.memno, 
a.name, 
a.addr1, 
a.addr2, 
a.city, 
a.state, 
a.zip, 
a.sex, 
a.lname, 
a.ssan, 
b.addr1 as old_addr1, 
b.addr2 as old_addr2, 
b.city as old_city, 
b.state as old_state, 
b.zip as old_zip, 
b.timec 

FROM Library2.Table1 a, Library2.Table2 b 
WHERE a.memno = b.memno and 
b.groupid = 'N2' and 
b.type = 'B' and 
b.datec = 20131209 
AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip) 

ORDER BY timec desc

My Code:

    private void getNumPrinted()
            {
                string qryCmd = "";
                OdbcDataReader dr;

                if (cnt > 1)
                {
                    switch (cmbLetterType.SelectedIndex)
                    {
                        case 0:
                            docType = "oldAddr";
                            qryCmd = buildSearchQuery(docType);
                            break;
                        case 1:
                            docType = "newAddr";
                            qryCmd = buildSearchQuery(docType);
                            break;
                        case 2:
                            docType = "nameChg";
                            qryCmd = buildSearchQuery(docType);
                            break;
                    }

                    string query = "";

                    if (qryCmd.Contains("INNER JOIN"))
                    {
                        var newQry = qryCmd.Replace(qryCmd.Substring(0, qryCmd.IndexOf("FROM TableC c") - 1), "SELECT COUNT(a.memno) AS RecCount");
                        var orderByIndex = newQry.IndexOf("ORDER BY");
                        newQry = newQry.Replace(newQry.Substring(orderByIndex, newQry.Length - orderByIndex), "");
                        query = newQry;


   }
                else
                {
                    var newQry = qryCmd.Replace(qryCmd.Substring(0, qryCmd.IndexOf("FROM") - 1), "SELECT COUNT(*) AS RecCount");
                    var orderByIndex = newQry.IndexOf("ORDER BY");
                    newQry = newQry.Replace(newQry.Substring(orderByIndex, newQry.Length - orderByIndex), "");
                    query = newQry;
                }

                dr = mdl.GetData(query);
                while (dr.Read())
                {
                    lblNumPrinted.Text = "# out of " + dr["RecCount"].ToString() + " printed";
                }

                // NEED TO PERFORM ANOTHER QUERY COMBINED WITH TableC to see how many records have not been printed.

                mdl.closeConn();
                lblNumPrinted.Visible = true;
            }
            cnt++;
        }

After String Manipulation:

SELECT COUNT(*) AS RecCount 
FROM Library1.Table1 a, Library1.Table2 b 
WHERE a.memno = b.memno and 
b.groupid = 'P2' and 
b.type = 'B' and 
b.datec = 20131209 
AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip) 

UNION SELECT COUNT(*) AS RecCount 
FROM Library2.Table1 a, Library2.Table2 b 
WHERE a.memno = b.memno and 
b.groupid = 'N2' and 
b.type = 'B' and 
b.datec = 20131209 
AND (a.addr1 <> b.addr1 or a.addr2 <> b.addr2 or a.city <> b.city or a. state <> b.state or a.zip <> b.zip)

I could not figure out as mentioned why my above query after string manipulation was setting the label to a value of "# of 24 printed."

When I ran my query in Server Explorer however, I saw the issue. In code I am trying to receive a single COUNT, and my replace code line is changing both select clauses in the UNION to the new "SELECT COUNT(*) AS RecCount".

Server Explorer Results:

[RecCount]

[14]

[24]

Can someone show me what modification I need to do to my code/query that uses the BOTH datasource so that I receive a single RecCount of 38?

Answer 1

Enclose your existing pair of queries inside a common table expression and use that as the source that you want to total up.

with counts as (
SELECT COUNT(*) AS RecCount 
FROM Library1.Table1 a, Library1.Table2 b 
WHERE... 
UNION SELECT COUNT(*) AS RecCount 
FROM Library2.Table1 a, Library2.Table2 b 
WHERE...
)
select sum(RecCount) from counts;