select * from pg_foreign_table; case when 用法: CASE WHEN condition_1 THEN result_1 WHEN condition_2 THEN result_2 [WHEN ...] [ELSE result_n] END 在这种通用形式中,每个条件都是一个返回布尔值的表达式,true或者false。 如果条件的计算结果为true,则CASE表达式返回与条件对应的结果,而所有其他CASE...
concat_lower_or_upper---HELLO WORLD (1row)SELECTconcat_lower_or_upper(a=>'Hello', uppercase=>true, b=>'World'); concat_lower_or_upper---HELLO WORLD (1row) SELECT concat_lower_or_upper('Hello', 'World', uppercase => true); concat_lower_or_upper --- HELLO WORLD (1 row) 为了...
CASE WHEN (t_infomask & 128) > 0 THEN 't' END AS lock_only, CASE WHEN (t_infomask & 4096) > 0 THEN 't' END AS is_multi, CASE WHEN (t_infomask2 & 8192) > 0 THEN 't' END AS keys_upd, CASE WHEN (t_infomask & 16) > 0 THEN 't' END AS keyshr_lock, CASE WHEN (t_...
上述语句中,COALESCE函数将null值替换为0,然后再执行递增操作。 使用CASE语句:CASE语句可以根据条件执行不同的操作。可以在CASE语句中判断null值,并执行相应的递增操作。例如,假设有一个名为"count"的列,可以使用以下语句递增该列的值: 使用CASE语句:CASE语句可以根据条件执行不同的操作。可以在CASE语句中判断null值,...
选择相应的集合或者文件夹,并配置好运行规则,就可以批量运行请求了。 2. 导入数据 在运行集合的时候可以导入外部数据文件,文件格式可以是json也可以是CSV。这可以方便的导入更多的测试用例,增加测试的case覆盖度。 导入CSV数据格式: path, value post, 1 post, 2 post, 3 post, 4 1. 2....
( CASE WHEN att.attnum > 0 THEN 1 ELSE 0 END) <> count(s.attname) AS is_na FROM pg_attribute AS att JOIN pg_class AS tbl ON att.attrelid = tbl.oid JOIN pg_namespace AS ns ON ns.oid = tbl.relnamespace LEFT JOIN pg_stats AS s ON s.schemaname = ns.nspname AND s....
The MOD() function retrieves a negative remainder when a negative numerator is passed to the MOD() function. Example 4: MOD() Function With Negative Denominator In the below example, we pass a negative denominator to the MOD() function: ...
To generate an RSA key, for example, run:ssh-keygen -t rsa -m PEM -f myuser_rsaThe command produces the private key in PEM format and the public key remains in the standard format used by the authorized_keys file on your bastion server. Add the public key to your bastion host to ...
(for example in AWS RDS), uncomment the GRANT-- line below and replace <MASTER_USER> with your root user.-- GRANT postgres_exporter TO <MASTER_USER>;GRANT CONNECT ON DATABASE postgres TO postgres_exporter;GRANT pg_monitor to postgres_exporter;版本<10的pg,只执行下面的SQLCREATE SCHEMA IF ...
This allows, for example, the case of trying to * update a block that was later truncated away. */ if (zero_damaged_pages || InRecovery) MemSet(buffer, 0, BLCKSZ); else ereport(ERROR, (errcode(ERRCODE_DATA_CORRUPTED), errmsg("could not read block %u in file \"%s\": read only ...