View the number of fields in a table in the database

View the number of fields in a table in the database. query the total number of fields in a table in Oracle. Use an SQL statement or [html] select count (column_name) in PL/SQL) from user_tab_columns where table_name = 't_ B _auditor 'can be used to check the number of fields in the specified table.
The following is a rough view: select tname, count (*) from col group by tname; [html] Listen 64 limit 4 65 T_ B _AUDITOR 14 66 T_ B _BOOKMANAGEMENT 13 67 T_ B _BOOKSTATUSCONFIG 5 68 limit 8 69 T_ B _FILTERWORD 11 70 limit 11 71 T_ B _MODEL 10 72 T_ B _NOTICE 15 73 limit 11 74 T_ B _OPERLOG 10 75 T_ B _ORGANIZATIONINFO 18 76 T_ B _PREFIXINFO 15 77 T_ B _PUBLISHINFO 30 78 T_ B _ROLE 8 79 T_ B _R OLEMODEL 6 80 T_ B _SAMPLEBOOKINFO 89 81 T_ B _USER 26 82 T_ B _USERANDROLE 6 83 T_ B _USERLOGIN 8 84 T_ B _USERMODEL 6 now I think of mysql above: using functions directly to solve: [html] mysql> desc test; + --------- + ------------- + ------ + ----- + --------- + ---------------- + | Field | Type | Null | Key | Default | Extra | + --------- + ------------- + ------ + ----- + --------- + ---------------- + | id | int (11) | NO | PRI | NULL | auto_increment | name | Varchar (10) | YES | NULL | address | varchar (30) | YES | NULL | + --------- + ------------- + ------ + ----- + --------- + ---------------- + 3 rows in set (0.01 sec) mysql> select found_rows (); + -------------- + | found_rows () | + -------------- + | 3 | + -------------- + 1 row in set (0.01 sec) there is also the use of the system table: [html] mysql> use information_schema Database changed www.2cto.com mysql> select count (*) from col Umns where table_name = "test"; + ---------- + | count (*) | + ---------- + | 3 | + ---------- + 1 row in set (0.00 sec) in mysql, you want to know the number of databases in the database: [html] mysql> select * from schemata; + -------------- + ------------------ + upper + ---------- + | CATALOG_NAME | SCHEMA_NAME | DEFAULT_CHARACTER_SET_NAME | DEFAULT_COLLATION_NAME | SQL _PATH | + --------------- ----- + Keys + ---------- + | NULL | information_schema | utf8 | utf8_general_ci | NULL | mysql | utf8 | utf8_general_ci | NULL | test | utf8 | utf8_general_ci | NULL | + -------------- + -------------------- + ------------------------------ + ------------------------ + ---------- + 3 rows in set (0.00 sec) the number of tables in the mysql database: [html] mysql> select table _ Schema, count (*) from tables group by table_schema; + -------------------- + ---------- + www.2cto.com | table_schema | count (*) | + -------------------- + ---------- + | information_schema | 17 | mysql | 17 | test | 6 | + -------------------- + ---------- + 3 rows in set (0.00 sec) in fact, most databases and tables in the system table information_schema will have records. So study this table. Author: chen861201