DML

DML commands $D$ are added to the rules for expressions $e$ .

$$\begin{array}{rrcll} \textrm{Commands} & D &::=& (\mathsf{IN... ...trm{Table expressions} & T^E &::=& x \mid \{\{e\}\} \end{array}$$

Inside $\mathsf{UPDATE}$ and $\mathsf{DELETE}$ commands, lone variables $X$ are interpreted as references to columns of the implicit table $\mathsf{T}$ , rather than to named expressions.