![]() ![]() This property defaults to 'true’ which makes the driver send every string in Unicode format to the database by default. MS SQL JDBC drivers specify a configuration property called sendStringParametersAsUnicode which helps in getting rid of this unicode conversion. This would ultimately lead to a whole table scan during data fetch, thereby slowing down the search queries drastically. Moreover, if an index exists on the non-unicode column, it will be ignored. SQL Server tries to convert non-unicode datatypes in the table to unicode datatypes before doing the comparison. But, in cases where the data types of the columns do not support Unicode, serious performance issues arise especially during data fetches. The password that ColdFusion passes to the JDBC driver to connect to the data source if a ColdFusion application does not supply a password (for example, in a. ![]() ![]() In the case where the data types of the columns support Unicode, everything is smooth. By default, all Microsoft’s JDBC drivers send the strings in Unicode format to the SQL Server, irrespective of whether the datatype of the corresponding column defined in the SQL Server supports Unicode or not. For example, the character data types that support Unicode are nchar, nvarchar, longnvarchar where as their ASCII counter parts are char, varchar and longvarchar respectively. SQL Server differentiates its data types that support Unicode from the ones that just support ASCII. When writing JDBC clients for Microsoft SQL Server, we need to be fully aware of the default string conversions made by the JDBC drivers which can drastically hit the performance of the application/client. ![]()
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