实现快传，完善快传和网盘的功能，实现文件的互传等一系列功能

backend/sql/opengauss-init.sql

@@ -3,9 +3,7 @@ CREATE TABLE IF NOT EXISTS portal_user (
     username VARCHAR(64) NOT NULL UNIQUE,
     email VARCHAR(128) NOT NULL UNIQUE,
     password_hash VARCHAR(255) NOT NULL,
-    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
-    last_school_student_id VARCHAR(64),
-    last_school_semester VARCHAR(64)
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
 );
 
 CREATE TABLE IF NOT EXISTS portal_file (
@@ -21,33 +19,5 @@ CREATE TABLE IF NOT EXISTS portal_file (
     CONSTRAINT uk_portal_file_user_path_name UNIQUE (user_id, path, filename)
 );
 
-CREATE TABLE IF NOT EXISTS portal_course (
-    id BIGSERIAL PRIMARY KEY,
-    user_id BIGINT NOT NULL REFERENCES portal_user (id),
-    course_name VARCHAR(255) NOT NULL,
-    semester VARCHAR(64),
-    student_id VARCHAR(64),
-    teacher VARCHAR(255),
-    classroom VARCHAR(255),
-    day_of_week INTEGER,
-    start_time INTEGER,
-    end_time INTEGER,
-    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
-);
-
-CREATE TABLE IF NOT EXISTS portal_grade (
-    id BIGSERIAL PRIMARY KEY,
-    user_id BIGINT NOT NULL REFERENCES portal_user (id),
-    course_name VARCHAR(255) NOT NULL,
-    grade DOUBLE PRECISION NOT NULL,
-    semester VARCHAR(64) NOT NULL,
-    student_id VARCHAR(64),
-    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
-);
-
 CREATE INDEX IF NOT EXISTS idx_user_created_at ON portal_user (created_at);
 CREATE INDEX IF NOT EXISTS idx_file_created_at ON portal_file (created_at);
-CREATE INDEX IF NOT EXISTS idx_course_user_semester ON portal_course (user_id, semester, student_id);
-CREATE INDEX IF NOT EXISTS idx_course_user_created ON portal_course (user_id, created_at);
-CREATE INDEX IF NOT EXISTS idx_grade_user_semester ON portal_grade (user_id, semester, student_id);
-CREATE INDEX IF NOT EXISTS idx_grade_user_created ON portal_grade (user_id, created_at);