Correct comment on validateColumnDefaults

Author: zachmu

sql/analyzer/resolve_column_defaults.go

@@ -23,29 +23,8 @@ import (
 	"github.com/dolthub/go-mysql-server/sql/types"
 )
 
-// Resolving column defaults is a multi-phase process, with different analyzer rules for each phase.
-//
-//   - parseColumnDefaults: Some integrators (dolt but not GMS) store their column defaults as strings, which we need to
-//     parse into expressions before we can analyze them any further.
-//   - resolveColumnDefaults: Once we have an expression for a default value, it may contain expressions that need
-//     simplification before further phases of processing can take place.
-//
-// After this stage, expressions in column default values are handled by the normal analyzer machinery responsible for
-// resolving expressions, including things like columns and functions. Every node that needs to do this for its default
-// values implements `sql.Expressioner` to expose such expressions. There is custom logic in `resolveColumns` to help
-// identify the correct indexes for column references, which can vary based on the node type.
-//
-// Finally there are cleanup phases:
-//   - validateColumnDefaults: ensures that newly created column defaults from a DDL statement are legal for the type of
-//     column, various other business logic checks to match MySQL's logic.
-//   - stripTableNamesFromDefault: column defaults headed for storage or serialization in a query result need the table
-//     names in any GetField expressions stripped out so that they serialize to strings without such table names. Table
-//     names in GetField expressions are expected in much of the rest of the analyzer, so we do this after the bulk of
-//     analyzer work.
-//
-// The `information_schema.columns` table also needs access to the default values of every column in the database, and
-// because it's a table it can't implement `sql.Expressioner` like other node types. Instead it has special handling
-// here, as well as in the `resolve_functions` rule.
+// validateColumnDefaults ensures that newly created column defaults from a DDL statement are legal for the type of
+// column, various other business logic checks to match MySQL's logic.
 func validateColumnDefaults(ctx *sql.Context, _ *Analyzer, n sql.Node, _ *plan.Scope, _ RuleSelector, qFlags *sql.QueryFlags) (sql.Node, transform.TreeIdentity, error) {
 	span, ctx := ctx.Span("validateColumnDefaults")
 	defer span.End()