mac-docker-php容器连接mac中的pgsql数据库失败以及出现table_msg存错误时的解决方法

以php中的thinkphp 5.1为例，php容器连接mac中的pgsql数据库失败时，出现如下错误

[7] PDOException in Connection.php line 528
SQLSTATE[08006] [7] could not connect to server: Connection refused
Is the server running on host "localhost" (127.0.0.1) and accepting
TCP/IP connections on port 5432?

解决：以thinkphp 5.1为例，只需把 database.php 中的 hostname 改为 host.docker.internal 即可，然后，thinkphp 就能访问到数据库了。

return [
    // 数据库类型
    'type'            => 'pgsql',
    // 服务器地址
    'hostname'        => 'host.docker.internal'
];

如果可以访问后，再出现 table_msg(unknown) 如下错误时

SQLSTATE[42883]: Undefined function: 7 ERROR: function table_msg(unknown) does not exist
LINE 1: ...fault as "default",fields_default as "extra" from table_msg(...
^
HINT: No function matches the given name and argument types. You might need to add explicit type casts.

解决：在数据库中执行如下sql即可（因为 table_msg 函数需要用户自己定义）

CREATE OR REPLACE FUNCTION pgsql_type(a_type varchar) RETURNS varchar AS  
$BODY$  
DECLARE  
     v_type varchar;  
BEGIN  
     IF a_type='int8' THEN  
          v_type:='bigint';  
     ELSIF a_type='int4' THEN  
          v_type:='integer';  
     ELSIF a_type='int2' THEN  
          v_type:='smallint';  
     ELSIF a_type='bpchar' THEN  
          v_type:='char';  
     ELSE  
          v_type:=a_type;  
     END IF;  
     RETURN v_type;  
END;  
$BODY$  
LANGUAGE PLPGSQL;  
  
CREATE TYPE "public"."tablestruct" AS (  
  "fields_key_name" varchar(100),  
  "fields_name" VARCHAR(200),  
  "fields_type" VARCHAR(20),  
  "fields_length" BIGINT,  
  "fields_not_null" VARCHAR(10),  
  "fields_default" VARCHAR(500),  
  "fields_comment" VARCHAR(1000)  
);  
  
CREATE OR REPLACE FUNCTION "public"."table_msg" (a_schema_name varchar, a_table_name varchar) RETURNS SETOF "public"."tablestruct" AS  
$body$  
DECLARE  
     v_ret tablestruct;  
     v_oid oid;  
     v_sql varchar;  
     v_rec RECORD;  
     v_key varchar;  
BEGIN  
     SELECT  
           pg_class.oid  INTO v_oid  
     FROM  
           pg_class  
           INNER JOIN pg_namespace ON (pg_class.relnamespace = pg_namespace.oid AND lower(pg_namespace.nspname) = a_schema_name)  
     WHERE  
           pg_class.relname=a_table_name;  
     IF NOT FOUND THEN  
         RETURN;  
     END IF;  
  
     v_sql='  
     SELECT  
           pg_attribute.attname AS fields_name,  
           pg_attribute.attnum AS fields_index,  
           pgsql_type(pg_type.typname::varchar) AS fields_type,  
           pg_attribute.atttypmod-4 as fields_length,  
           CASE WHEN pg_attribute.attnotnull  THEN ''not null''  
           ELSE ''''  
           END AS fields_not_null,  
           pg_attrdef.adsrc AS fields_default,  
           pg_description.description AS fields_comment  
     FROM  
           pg_attribute  
           INNER JOIN pg_class  ON pg_attribute.attrelid = pg_class.oid  
           INNER JOIN pg_type   ON pg_attribute.atttypid = pg_type.oid  
           LEFT OUTER JOIN pg_attrdef ON pg_attrdef.adrelid = pg_class.oid AND pg_attrdef.adnum = pg_attribute.attnum  
           LEFT OUTER JOIN pg_description ON pg_description.objoid = pg_class.oid AND pg_description.objsubid = pg_attribute.attnum  
     WHERE  
           pg_attribute.attnum > 0  
           AND attisdropped <> ''t''  
           AND pg_class.oid = ' || v_oid || '  
     ORDER BY pg_attribute.attnum' ;  
  
     FOR v_rec IN EXECUTE v_sql LOOP  
         v_ret.fields_name=v_rec.fields_name;  
         v_ret.fields_type=v_rec.fields_type;  
         IF v_rec.fields_length > 0 THEN  
            v_ret.fields_length:=v_rec.fields_length;  
         ELSE  
            v_ret.fields_length:=NULL;  
         END IF;  
         v_ret.fields_not_null=v_rec.fields_not_null;  
         v_ret.fields_default=v_rec.fields_default;  
         v_ret.fields_comment=v_rec.fields_comment;  
         SELECT constraint_name INTO v_key FROM information_schema.key_column_usage WHERE table_schema=a_schema_name AND table_name=a_table_name AND column_name=v_rec.fields_name;  
         IF FOUND THEN  
            v_ret.fields_key_name=v_key;  
         ELSE  
            v_ret.fields_key_name='';  
         END IF;  
         RETURN NEXT v_ret;  
     END LOOP;  
     RETURN ;  
END;  
$body$  
LANGUAGE 'plpgsql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;  
  
COMMENT ON FUNCTION "public"."table_msg"(a_schema_name varchar, a_table_name varchar)  
IS '获得表信息';  
  
---重载一个函数  
CREATE OR REPLACE FUNCTION "public"."table_msg" (a_table_name varchar) RETURNS SETOF "public"."tablestruct" AS  
$body$  
DECLARE  
    v_ret tablestruct;  
BEGIN  
    FOR v_ret IN SELECT * FROM table_msg('public',a_table_name) LOOP  
        RETURN NEXT v_ret;  
    END LOOP;  
    RETURN;  
END;  
$body$  
LANGUAGE 'plpgsql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;  
  
COMMENT ON FUNCTION "public"."table_msg"(a_table_name varchar)  
IS '获得表信息';