But I spent a lot of time trying to understand why using a variable in a \copy command failed ... until a colleague of mine showed me this was actually written elsewhere in the documentation (formerly in the \copy chapter).
The first sentence of this SQL interpolation chapter says "A key feature of psql variables is that you can substitute (“interpolate”) them into regular SQL statements, as well as the arguments of meta-commands." But nothing in this chapter indicates that there are exceptions.
May be we could have a wording adjustment with something like : "A key feature of psql variables is that you can substitute (“interpolate”) them into regular SQL statements, as well as the arguments of meta-commands (unless specifically noted)."
+1
or maybe better - if it is possible reduce a exceptions
Pavel
Regards. Philippe.
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