FIX: Remove unused decimal separator code and add regression tests (#384)

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GitHub Issue: #295

-------------------------------------------------------------------
### Summary   
Removes misleading unused decimal-separator code from the bulk fetch
path and adds a regression test to ensure DECIMAL values are parsed
correctly regardless of setDecimalSeparator().



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---------

Co-authored-by: Gaurav Sharma <sharmag@microsoft.com>

Author: Chetan-Kansal

mssql_python/logging.py

@@ -17,7 +17,6 @@
 import atexit
 from typing import Optional
 
-
 # Single DEBUG level - all or nothing philosophy
 # If you need logging, you need to see everything
 DEBUG = logging.DEBUG  # 10

mssql_python/pybind/ddbc_bindings.cpp

@@ -2892,7 +2892,7 @@ SQLRETURN SQLGetData_wrap(SqlHandlePtr StatementHandle, SQLUSMALLINT colCount, p
     SQLHSTMT hStmt = StatementHandle->get();
 
     // Cache decimal separator to avoid repeated system calls
-    std::string decimalSeparator = GetDecimalSeparator();
+
 
     for (SQLSMALLINT i = 1; i <= colCount; ++i) {
         SQLWCHAR columnName[256];
@@ -3615,7 +3615,7 @@ SQLRETURN FetchBatchData(SQLHSTMT hStmt, ColumnBuffers& buffers, py::list& colum
             columnInfos[col].processedColumnSize + 1;  // +1 for null terminator
     }
 
-    std::string decimalSeparator = GetDecimalSeparator();  // Cache decimal separator
+
 
     // Performance: Build function pointer dispatch table (once per batch)
     // This eliminates the switch statement from the hot loop - 10,000 rows × 10

tests/test_001_globals.py

@@ -388,8 +388,7 @@ def test_decimal_separator_with_db_operations(db_connection):
     try:
         # Create a test table with decimal values
         cursor = db_connection.cursor()
-        cursor.execute(
-            """
+        cursor.execute("""
         DROP TABLE IF EXISTS #decimal_separator_test;
         CREATE TABLE #decimal_separator_test (
             id INT,
@@ -400,8 +399,7 @@ def test_decimal_separator_with_db_operations(db_connection):
             (2, 678.90),
             (3, 0.01),
             (4, 999.99);
-        """
-        )
+        """)
         cursor.close()
 
         # Test 1: Fetch with default separator
@@ -469,8 +467,7 @@ def test_decimal_separator_batch_operations(db_connection):
     try:
         # Create test data
         cursor = db_connection.cursor()
-        cursor.execute(
-            """
+        cursor.execute("""
         DROP TABLE IF EXISTS #decimal_batch_test;
         CREATE TABLE #decimal_batch_test (
             id INT,
@@ -481,8 +478,7 @@ def test_decimal_separator_batch_operations(db_connection):
             (1, 123.456, 12345.67890), 
             (2, 0.001, 0.00001),
             (3, 999.999, 9999.99999);
-        """
-        )
+        """)
         cursor.close()
 
         # Test 1: Fetch results with default separator

tests/test_003_connection.py

@@ -992,16 +992,14 @@ def test_execute_with_large_parameters(db_connection, conn_str):
         pytest.skip("Skipping for Azure SQL - large parameter tests may cause timeouts")
 
     # Test with a temporary table for large data
-    cursor = db_connection.execute(
-        """
+    cursor = db_connection.execute("""
     DROP TABLE IF EXISTS #large_params_test;
     CREATE TABLE #large_params_test (
         id INT,
         large_text NVARCHAR(MAX),
         large_binary VARBINARY(MAX)
     )
-    """
-    )
+    """)
     cursor.close()
 
     try:
@@ -2126,12 +2124,10 @@ def test_timeout_long_query(db_connection):
                     while retry_count < max_retries:
                         start_time = time.perf_counter()
                         try:
-                            cursor.execute(
-                                """
+                            cursor.execute("""
                             SELECT COUNT(*) FROM sys.objects a, sys.objects b, sys.objects c
                             WHERE a.object_id = b.object_id * c.object_id
-                            """
-                            )
+                            """)
                             cursor.fetchall()
                             elapsed_time = time.perf_counter() - start_time
                             break  # Success, exit retry loop