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ProvSQL C/C++ API
Adding support for provenance and uncertainty management to PostgreSQL databases
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ProvSQL C/C++ API
Adding support for provenance and uncertainty management to PostgreSQL databases
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Report an implicit freezing: a part of the statement evaluated as plain SQL on the data as it is, not tracked. More...
Public Attributes | |
| Node * | target |
| bool | found |
Report an implicit freezing: a part of the statement evaluated as plain SQL on the data as it is, not tracked.
frozen is that part (a subquery expression), or NULL when it is computed from the rows of the query itself (a window value, the cut of a LIMIT), which then reads the relations the rest tracks. The freezing is coherent when the frozen part reads no base relation that the rest of the statement tracks (a relation with no recorded base relations counts as all of them): the result is then the provenance of the statement with the frozen relations untracked. An incoherent freezing is refused under provsql.implicit_freeze = 'error', a warning otherwise, naming a relation read both ways.
| msg | What is frozen, the message |
| hint | How to say it is meant, or NULL for the plain() marker |
Context for holds_node_walker.