SQL

CREATE TABLE textbook_units  (
  id          INTEGER PRIMARY KEY AUTOINCREMENT,
  version_id  TEXT NOT NULL REFERENCES textbook_versions(id),
  unit_order  INTEGER NOT NULL,
  -- 单元序号
    title       TEXT NOT NULL,
  -- 单元标题
    unit_type   TEXT DEFAULT 'regular',
  -- regular/识字/拼音/习作/综合
    created_at  DATETIME DEFAULT (datetime('now'))
)

+ Add column

Columns

Column Data type Allow null Primary key Actions
id INTEGER ✓ ✓ Rename | Drop
version_id TEXT Rename | Drop
unit_order INTEGER Rename | Drop
title TEXT Rename | Drop
unit_type TEXT ✓ Rename | Drop
created_at DATETIME ✓ Rename | Drop

Foreign Keys

Column Destination
version_id textbook_versions.id

+ Add index

Indexes

Name Columns Unique SQL Drop?
idx_units_version version_id SQL 
CREATE INDEX idx_units_version
ON textbook_units(version_id)
Drop