feat: get comment & send post

migrations/2022-03-15-104943_create_comments/down.sql

@@ -0,0 +1,3 @@
+-- This file should undo anything in `up.sql`
+
+DROP TABLE comments

migrations/2022-03-15-104943_create_comments/up.sql

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+-- Your SQL goes here
+
+CREATE TABLE comments (
+  id INTEGER NOT NULL PRIMARY KEY,
+  author_hash VARCHAR NOT NULL,
+  author_title VARCHAR(10) NOT NULL DEFAULT '',
+  content TEXT NOT NULL,
+  create_time TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  is_deleted BOOLEAN NOT NULL DEFAULT FALSE,
+  post_id INTEGER NOT NULL,
+  FOREIGN KEY(post_id) REFERENCES post(id)
+);
+CREATE INDEX comments_postId_idx ON comments (`post_id`);
+