CREATE TABLE wallet_transactions (
                                     id BIGINT PRIMARY KEY,
                                     user_id BIGINT NOT NULL,
                                     type VARCHAR(20) NOT NULL,
                                     amount DECIMAL(12,2) NOT NULL,
                                     balance_after DECIMAL(12,2) NOT NULL,
                                     description VARCHAR(500) NOT NULL,
                                     order_id BIGINT,
                                     created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
                                     search_text TEXT GENERATED ALWAYS AS (
                                         type || ' ' || description
                                         ) STORED,

                                     CONSTRAINT chk_transaction_type CHECK (type IN ('topup', 'payment', 'income', 'withdrawal', 'refund'))
);

-- 基础索引
CREATE INDEX idx_transactions_user ON wallet_transactions(user_id, created_at DESC);
CREATE INDEX idx_transactions_order ON wallet_transactions(order_id) WHERE order_id IS NOT NULL;
CREATE INDEX idx_transactions_type ON wallet_transactions(user_id, type, created_at DESC);

-- 三元组索引用于交易描述搜索
CREATE INDEX idx_transactions_search_trgm ON wallet_transactions USING gin(search_text gin_trgm_ops);

-- 复合索引优化用户交易查询
CREATE INDEX idx_transactions_user_type_created ON wallet_transactions(user_id, type, created_at DESC);

-- 时间范围索引 (用于统计)
CREATE INDEX idx_transactions_created_amount ON wallet_transactions(created_at DESC, amount);

-- 订单关联索引
CREATE INDEX idx_transactions_order_type ON wallet_transactions(order_id, type)
    WHERE order_id IS NOT NULL;