Andy Tompkins wrote:
eg: stringstream << select << column("c1") << column("table1", "column2") << from << table("table1").as("t1");
=> "SELECT [c1], [t1].[column2] FROM [table1] AS [t1]"
I believe that a database library for boost should include something like this.
A good idea, but IMO you haven't taken it far enough. First, consider the RTL, the relational template library (http://sdmg.developerpipeline.com/documents/s=9849/cuj0403vertleyb/), which gives you strong type-safety when applying relational operations to strongly-typed in-memory data. It uses expression templates. Next, consider xpressive, which allows you to author regular expressions either as expression templates OR as strings. It makes use of a generic expression template manipulation framework called proto, which makes it fairly straightword to define arbitrary transformations on a statically typed expression tree. Now, putting it all together, I imagine a relational library with a dual-interface like xpressive, but for SQL instead of regex. SQL statements could be expression templates, which when applied to in-memory data, yields strongly-typed results. OR, the exact same expression template, when used in a different context, might get transformed into the equivalent SQL string for remote (lazy?) execution with dynamic typing. Potentially very powerful. -- Eric Niebler Boost Consulting www.boost-consulting.com