fix: let sqlc output nullable array

Close #1851

This remove 2 assumptions from the code:
- type cast are no longer always non null
- postgres can output nullable array

Author: babariviere

internal/codegen/golang/postgresql_type.go

@@ -36,7 +36,7 @@ func parseIdentifierString(name string) (*plugin.Identifier, error) {
 
 func postgresType(req *plugin.GenerateRequest, options *opts.Options, col *plugin.Column) string {
 	columnType := sdk.DataType(col.Type)
-	notNull := col.NotNull || col.IsArray
+	notNull := col.NotNull
 	driver := parseDriver(options.SqlPackage)
 	emitPointersForNull := driver.IsPGX() && options.EmitPointersForNullTypes
 

internal/compiler/resolve.go

@@ -512,7 +512,7 @@ func (comp *Compiler) resolveCatalogRefs(qc *QueryCatalog, rvs []*ast.RangeVar,
 				return nil, fmt.Errorf("*ast.TypeCast has nil type name")
 			}
 			col := toColumn(n.TypeName)
-			defaultP := named.NewInferredParam(col.Name, col.NotNull)
+			defaultP := named.NewInferredParam(col.Name, false)
 			p, _ := params.FetchMerge(ref.ref.Number, defaultP)
 
 			col.Name = p.Name()