PostgreSQL中pg_surgery的扩展使用

-- 安装扩展
CREATE EXTENSION pg_surgery;

-- 验证安装
SELECT * FROM pg_available_extensions WHERE name = 'pg_surgery';

-- 修复包含损坏元组的表
SELECT heap_force_kill('my_table'::regclass, ARRAY['(0,1)']::tid[]);

-- 处理事务ID回卷问题
SELECT heap_force_freeze('problem_table'::regclass, ARRAY['(0,1)']::tid[]);

-- 修复损坏的B-tree索引
SELECT btree_force_options('my_index'::regclass, ARRAY['fastupdate=off']);

-- 将卡住的事务标记为已提交
SELECT txid_force_status(123456, 'committed');

-- 1. 首先识别损坏的元组
SELECT ctid, * FROM my_table WHERE ...; -- 返回错误

-- 2. 强制删除损坏元组
SELECT heap_force_kill('my_table'::regclass, ARRAY['(0,1)']::tid[]);

-- 3. 重建表
VACUUM FULL my_table;

-- 1. 识别需要冻结的元组
SELECT ctid, xmin, xmax FROM problem_table 
WHERE age(xmin) > 2000000000;

-- 2. 强制冻结这些元组
SELECT heap_force_freeze(
  'problem_table'::regclass,
  ARRAY(SELECT ctid::text::tid 
        FROM problem_table 
        WHERE age(xmin) > 2000000000)
);

-- 3. 执行常规VACUUM
VACUUM problem_table;

-- 在单用户模式下使用：
postgres --single -D /path/to/data/directory dbname

-- 修复系统目录不一致
SELECT pg_surgery_function(...);

pg_basebackup -D /backup/location -X stream

CREATE TABLE surgery_audit AS
SELECT now(), current_user, * FROM pg_surgery_function(...);

REVOKE ALL ON FUNCTION heap_force_kill FROM PUBLIC;
GRANT EXECUTE ON FUNCTION heap_force_kill TO dbadmin;

-- 检查表完整性
ANALYZE repaired_table;

-- 验证索引
SELECT indexrelid::regclass, indisvalid 
FROM pg_index WHERE indrelid = 'repaired_table'::regclass;