scanner

Overview ¶

Package scanner maps *sql.Rows into Go values for sqlx.

Public helpers such as github.com/xoctopus/sqlx/pkg/helper.Scan and QueryAndScan delegate here. Adaptor catalog loaders also use Scan to read information_schema rows into structs.

Scan ¶

err := scanner.Scan(ctx, rows, &user)   // single row; NOTFOUND if empty
err := scanner.Scan(ctx, rows, &users)  // []T appends each row
err := scanner.Scan(ctx, rows, &count)  // scalar / sql.Scanner

Scan closes rows when finished. The destination must be a pointer (or a custom ScanIter). Empty rows with a single-value target return the package errors NOTFOUND code.

Destination shapes ¶

• struct pointer: match row columns to `db` fields (and table__column aliases from joins via frag.Alias); NULL columns are skipped via nullable.NullIgnoreScanner
• WithColumnReceivers: explicit column-name → scan target map
• sql.Scanner / scalar pointer: rows.Scan into that value
• slice pointer: one New/Next cycle per row (SliceScanIter)
• ScanIter: custom New + Next pipeline (ScanIterFor)

Unmatched columns are discarded (nullable.EmptyScanner).

nullable ¶

Subpackage nullable provides nullable.NullIgnoreScanner (nil src leaves the destination unchanged) and EmptyScanner for unused columns.