Module sql 

What kind of answer an SQL statement expects, from its leading keyword.

The SQL servers (postgresql, mysql) hand the model the statement text and three ways to answer it: a result set, a command tag / OK packet, or an error. The real-model eval showed a small model answering SELECT current_user with the command tag INSERT 0 1 — copied from the ok action’s example — so the client got “INSERT 0 1” for a query that asked for a value. Both servers know the statement exactly, so each tells the model which shape answers it (answer_with in the event) instead of leaving it to map SQL to the wire in its head.

This is a classifier over the first keyword, not a parser: it reads past leading whitespace, -- and /* */ comments and opening parentheses, and nothing else. A statement it cannot place is StatementShape::Unknown, and the caller says nothing rather than guess.

Enums

StatementShape

The answer a statement’s leading keyword calls for.

Functions

statement_shape

Classify sql by its first keyword. See the module docs for what “first” means.