adjust sql_data_type and column_size for NULL parameters

[gjcarrette]

This is a proposed fix for #1310

[codecov]

Codecov Report

Merging #1311 (2b92d28) into dev (36d2704) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##              dev    #1311   +/-   ##
=======================================
  Coverage   83.41%   83.42%           
=======================================
  Files          22       22           
  Lines        7822     7824    +2     
=======================================
+ Hits         6525     6527    +2     
  Misses       1297     1297           

Impacted Files	Coverage Δ
...phpdev/vs16/x86/php-8.0.11-src/ext/sqlsrv/util.cpp
...php-8.0.11-src/ext/pdo_sqlsrv/shared/core_stmt.cpp
...phpdev/vs16/x86/php-8.0.11-src/ext/sqlsrv/init.cpp
...s16/x86/php-8.0.11-src/ext/pdo_sqlsrv/pdo_util.cpp
...php-8.0.11-src/ext/pdo_sqlsrv/shared/core_util.cpp
...phpdev/vs16/x86/php-8.0.11-src/ext/sqlsrv/stmt.cpp
...s16/x86/php-8.0.11-src/ext/pdo_sqlsrv/pdo_init.cpp
...-8.0.11-src/ext/pdo_sqlsrv/shared/core_results.cpp
...x86/php-8.0.11-src/ext/sqlsrv/shared/core_stmt.cpp
...x86/php-8.0.11-src/ext/sqlsrv/shared/core_util.cpp
... and 34 more

[yitam]

@gjcarrette

Please make changes to the method sqlsrv_param::process_null_param() instead (line 2146), because that is for input parameters:

--- a/source/shared/core_stmt.cpp
+++ b/source/shared/core_stmt.cpp
@@ -2151,13 +2151,13 @@ void sqlsrv_param::process_null_param(_Inout_ zval* param_z)
         // if the server type is a binary type, than the server expects the sql_type to be binary type
         // as well, otherwise an error stating "Implicit conversion not allowed.." is thrown by the
         // server. For all other server types, setting the sql_type to sql_char works fine.
-        sql_data_type = (encoding == SQLSRV_ENCODING_BINARY) ? SQL_BINARY : SQL_CHAR;
+        sql_data_type = (encoding == SQLSRV_ENCODING_BINARY) ? SQL_BINARY : SQL_VARCHAR;
     }

     c_data_type = (encoding == SQLSRV_ENCODING_BINARY) ? SQL_C_BINARY : SQL_C_CHAR;

     if (column_size == SQLSRV_UNKNOWN_SIZE) {
-        column_size = 1;
+        column_size = (encoding == SQLSRV_ENCODING_BINARY) ? 1 : 0;
         decimal_digits = 0;
     }
     buffer = NULL;

[yitam]

@gjcarrette any update? Would you want me to make the suggested changes?

[gjcarrette]

Yes, that makes sense, because the SQLRelay source file odbc.cpp that I mentioned in the issue also uses SQL_C_BINARY for both binary or non-binary T-SQL NULL.

So one thing we didn't do here is make a phpt file, a test case, that fails with the old code but passes with the new code.
To tell the truth I did not use the make test targets in the msphpsql tree, I used the test file that I distributed with the issue.

[yitam]

Thanks @gjcarrette this looks good.

[lelia]

Hello @yitam, I'm reaching out from Wayfair's Open Source Program Office. We're holding a company-wide Hacktoberfest event, and were hoping to recognize @gjcarrette's contribution here as part of the festivities.

In order to receive full credit for Hacktoberfest, accepted PRs must include a hacktoberfest-accepted label. Is there any chance you could apply that label to this PR so we can more easily highlight this contribution? Thanks so much.

[yitam]

Done @lelia

[lelia]

Fantastic. Thanks again @yitam !