如何在postgresql中获取更新、插入、删除查询的行数

Question

我有一个 postgresql tables。用户可以使用界面或使用查询手动更新或删除记录。我需要跟踪有多少记录已更新，已删除到日志中 table.I 已经尝试过，因为可以成功跟踪以下更新操作计数。但是删除操作计数没有记录到日志 table.

CREATE OR REPLACE FUNCTION edmonton.count_func() RETURNS TRIGGER AS $body$
DECLARE
v_old_data TEXT;
v_new_data TEXT;
log_count INTEGER;
BEGIN


IF (TG_OP = 'UPDATE') THEN
v_old_data := ROW(OLD.*);
v_new_data := ROW(NEW.*);
log_count = count(row(new));
RAISE NOTICE 'update operations';
INSERT INTO edmonton.log ("timestamp",message,type,project_area,count)
VALUES (CURRENT_TIMESTAMP,'records updated in Builder 
table','Information','edmonton',log_count);
RETURN NEW;
ELSIF (TG_OP = 'DELETE') THEN
v_old_data := ROW(OLD.*);
log_count = count(row(old));
RAISE NOTICE 'delete operations';
INSERT INTO edmonton.log ("timestamp",message,type,project_area,count)
VALUES (CURRENT_TIMESTAMP,'records deleted in Builder 
table','Information','edmonton',log_count);
RETURN OLD;
ELSIF (TG_OP = 'INSERT') THEN
v_new_data := ROW(NEW.*);
log_count = count(row(new));
RAISE NOTICE 'insert operations';
INSERT INTO edmonton.log ("timestamp",message,type,project_area,count)
VALUES (CURRENT_TIMESTAMP,'records inserted in Builder 
table','Information','edmonton',log_count);
RETURN NEW;
ELSE
RAISE WARNING '[EDMONTON.COUNT_FUNC] - Other action occurred: %, at 
%',TG_OP,now();
RETURN NULL;
END IF;

EXCEPTION
WHEN data_exception THEN
RAISE WARNING '[EDMONTON.COUNT_FUNC] - UDF ERROR [DATA EXCEPTION] - 
SQLSTATE: %, SQLERRM: %',SQLSTATE,SQLERRM;
RETURN NULL;
WHEN unique_violation THEN
RAISE WARNING '[EDMONTON.COUNT_FUNC] - UDF ERROR [UNIQUE] - SQLSTATE: %, 
SQLERRM: %',SQLSTATE,SQLERRM;
RETURN NULL;
WHEN OTHERS THEN
RAISE WARNING '[EDMONTON.COUNT_FUNC] - UDF ERROR [OTHER] - SQLSTATE: %, 
SQLERRM: %',SQLSTATE,SQLERRM;
RETURN NULL;
END;
$body$
LANGUAGE plpgsql
 SECURITY DEFINER
SET search_path = pg_catalog, edmonton;

这是我的触发器

CREATE TRIGGER count_audit
AFTER INSERT OR UPDATE OR DELETE
ON edmonton.builder
FOR EACH STATEMENT
EXECUTE PROCEDURE edmonton.count_func();

我在更新记录时收到一条警告消息，并且消息未记录到日志 table。

WARNING:  [EDMONTON.COUNT_FUNC] - UDF ERROR [OTHER] - SQLSTATE: 55000, SQLERRM: record "old" is not assigned yet
CONTEXT:  PL/pgSQL function count_func() line 49 at RAISE

Answer 1

https://www.postgresql.org/docs/current/static/plpgsql-trigger.html

NEW

Data type RECORD; variable holding the new database row for INSERT/UPDATE operations in row-level triggers. This variable is unassigned in statement-level triggers and for DELETE operations.

OLD

Data type RECORD; variable holding the old database row for UPDATE/DELETE operations in row-level triggers. This variable is unassigned in statement-level triggers and for INSERT operations.

所以真正的问题是

how does update/insert work?..

Answer 2

首先，您无法以这种方式计算 inserted/updated/deleted 行。表达式

count(row(new))

总是 returns 1 因为 row(new) 是单行。

其次，记录new和old没有在每个语句的触发器中设置。每 the documentation:

NEW

Data type RECORD; variable holding the new database row for INSERT/UPDATE operations in row-level triggers. This variable is unassigned in statement-level triggers and for DELETE operations.

如何在postgresql中获取更新、插入、删除查询的行数

How to get the row count of update,insert,delete query in postgresql

sql

postgresql

plpgsql

postgresql-9.3