SqlMapping

Data structure managing DB table and column aliases.

Aliases are scoped by the result path, which is unique in the GraphQL output even in the presence of GraphQL field alises. Table aliases apply from the given output path and below.

Column aliases are synthesized whenever an SQL union has to be nested in a subquery and hence requires a uniform set of column names. These column aliases apply from the given path and above.

Tables are only aliased if they have already been seen in an depth-first in-order traversal of the output graph. This data structure also track the seen state for tables.

AliasedMappings also maintains the bookeeping information needed to supply arbitrary fresh names. Currently these are used to name identity/predicate joins.

Name of a SQL schema column and its associated codec. Note that Columns are considered equal if their table and column names are equal.

A pair of ColumnRefs, representing a SQL join.

Cursor positioned at a GraphQL result leaf

Represents the mapping of a GraphQL query to an SQL query

Cursor positioned at a GraphQL result non-leaf

Common super type for mappings which have a programmatic discriminator, ie. interface and union mappings. TODO: support SQL-native discriminators.

Representation of a SQL query in a context

Representation of a table expression

Root mappings can perform a mutation prior to constructing the result Cursor. A Mutation may perform a Unit effect and simply return the passed arguments; or it may refine the passed Query and/or Env that will be used to interpret the resulting Cursor.

Typeclass for SQL fragments.

The type of a codec that reads and writes column values of type A.

The type of an encoder that writes column values of type A.

The type of a fragment of SQL together with any interpolated arguments.

Extract an encoder from a codec.