fix(tools/postgres-execute-sql): do not ignore SQL failure (#1829)

## Description

Invalid SQL like selecting from invalid tables or granting bad
permissions resulted in a null due to the missing error statement.

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🛠️ Fixes #1638

internal/tools/postgres/postgresexecutesql/postgresexecutesql.go

@@ -126,12 +126,13 @@ func (t Tool) Invoke(ctx context.Context, params tools.ParamValues, accessToken
 	if err != nil {
 		return nil, fmt.Errorf("error getting logger: %s", err)
 	}
-	logger.DebugContext(ctx, "executing `%s` tool query: %s", kind, sql)
+	logger.DebugContext(ctx, fmt.Sprintf("executing `%s` tool query: %s", kind, sql))
 
 	results, err := t.Pool.Query(ctx, sql)
 	if err != nil {
 		return nil, fmt.Errorf("unable to execute query: %w", err)
 	}
+	defer results.Close()
 
 	fields := results.FieldDescriptions()
 
@@ -148,6 +149,10 @@ func (t Tool) Invoke(ctx context.Context, params tools.ParamValues, accessToken
 		out = append(out, vMap)
 	}
 
+	if err := results.Err(); err != nil {
+		return err.Error(), fmt.Errorf("unable to execute query: %w", err)
+	}
+
 	return out, nil
 }
 

tests/tool.go

@@ -746,6 +746,20 @@ func RunExecuteSqlToolInvokeTest(t *testing.T, createTableStatement, select1Want
 			requestBody:   bytes.NewBuffer([]byte(fmt.Sprintf(`{"sql": %s}`, configs.select1Statement))),
 			isErr:         true,
 		},
+		{
+			name:          "invoke my-exec-sql-tool with invalid SELECT SQL",
+			api:           "http://127.0.0.1:5000/api/tool/my-exec-sql-tool/invoke",
+			requestHeader: map[string]string{},
+			requestBody:   bytes.NewBuffer([]byte(`{"sql":"SELECT * FROM non_existent_table"}`)),
+			isErr:         true,
+		},
+		{
+			name:          "invoke my-exec-sql-tool with invalid ALTER SQL",
+			api:           "http://127.0.0.1:5000/api/tool/my-exec-sql-tool/invoke",
+			requestHeader: map[string]string{},
+			requestBody:   bytes.NewBuffer([]byte(`{"sql":"ALTER TALE t ALTER COLUMN id DROP NOT NULL"}`)),
+			isErr:         true,
+		},
 	}
 	for _, tc := range invokeTcs {
 		t.Run(tc.name, func(t *testing.T) {