JSON Support in Sql Server 2016 CTP3.2 – Quick Start

The JSON has landed (in beta at least) – and I think it’s now some practical use. I’ve collected a few technical references here. There may not be a native JSON type yet, but there are workarounds to provide the kind of assurance control-freak RDBMS developers find comforting. I’ve shown some of them in the code sample below. Continue reading

Simplify Reconciliation Code with Filtered Indexes

Some hand-matching of internal/external records may be needed even in an automated reconciliation. The matches will be stored in a database. Rules on matching can be enforced in the application, but there are often good reasons to place them in the database. In Sql Server, a filtered index (with a WHERE clause, in this case excluding Nulls) on the table can make this easier and more correct. Continue reading

Sql Server Filtered Index as a Unique Constraint on a Specific Value

Indexes often double as constraints. Each combination of values must only appear once among the columns of an index defined as UNIQUE. The “filtered” index allows some refinement. Suppose that in one column you won’t allow a specific value to appear more than once, but you don’t mind other values being duplicated.

A good example would be the IS_LATEST_VERSION column in a data warehouse table. Continue reading