order by table_rows desc) as b where b.table_name like 'sj_demo%' or b.table_name like 'sj_onlyinv' 2.查询wangdaisj数据库里以sj_demo为开头的所有表的表明 SELECT table_name FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA ='wangdaisj' and table_name like 'sj_demo%'" information_s...
FROM information_schema.tables WHERE table_schema = 'test' ORDER BY table_name DESC; 解释: 对表的meta data的查询需要使用information_schema.tables, table_schema是数据库的名称,table_name是具体的表明,table_type指的是表的类型 2. 检查数据库'test'中的某一个表'd_ad'是否存在 select count(1) from...
SQL(Structured Query Language,结构化查询语言)是使用关系模型的数据库应用语言, 与数据直接打交道 ,由 IBM 上世纪70年代开发出来。后由美国国家标准局(ANSI)开始着手制定SQL标准,先后有 SQL-86 , SQL-89 , SQL-92 , SQL-99 等标准。 SQL 有两个重要的标准,分别是 SQL92 和 SQL99,它们分别代表了 92 年...
connection.query("SELECT DATABASE() AS tableSchema",function(error,results,fields){if(error)throwerror;// 处理查询结果}); 1. 2. 3. 4. 这里的"SELECT DATABASE() AS tableSchema"是查询语句,它将查询当前数据库的名字,并将结果命名为tableSchema。 4. 获取查询结果 在查询完成后,我们可以通过回调函...
TABLE_SCHEMA query Posted by:Erik Lee Date: February 07, 2017 10:10PM select table_name, table_schema from information_schema.tables where TABLE_SCHEMA like 'Net%' -- Can someone point out why the TABLE_SCHEMA column is displayed like so:-...
A more accurate method of obtaining this information in such cases is to query the INFORMATION_SCHEMA PARTITIONS table, as shown in this example: SELECT SUM(DATA_FREE) FROM INFORMATION_SCHEMA.PARTITIONS WHERE TABLE_SCHEMA = 'mydb' AND TABLE_NAME = 'mytable'; For more information, see ...
WHERE TABLE_SCHEMA='your_database_name'AND TABLE_NAME='your_table_name'; 以上SQL 语句中的 'your_database_name' 和 'your_table_name' 分别是你的数据库名和表名。 查看外键信息: SELECT TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME,REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME ...
mysql>SETsql_mode='ANSI';Query OK, 0 rows affected (0.00 sec)mysql>CREATEVIEWtest.vASSELECT'a'||'b'ascol1;Query OK, 0 rows affected (0.00 sec)mysql>SELECTVIEW_DEFINITIONFROMINFORMATION_SCHEMA.VIEWSWHERETABLE_SCHEMA='test'ANDTABLE_NAME='v';+---+|VIEW_DEFINITION|+---+|select concat('...
2017-12-29T12:33:33.095243Z 2 Query SELECT TABLE_SCHEMA, TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE CREATE_OPTIONS LIKE '%partitioned%'; 切割后的字段列表如下: MySQL 慢查询日志 日志原文: # Time: 2019-11-27T10:43:13.460744Z # User@Host: root[root] @ localhost [1.2.3.4] Id: 35 ...
root@localhost : (none) 11:57:28> SELECT * FROM INFORMATION_SCHEMA.OPTIMIZER_TRACE\G; *** 1. row *** QUERY: select * from sbtest.sbtest1 where id=1 TRACE: { "steps": [ { "join_preparation": { "select#": 1, "steps": [ {...