Original address: http://my.oschina.net/zimingforever/blog/64145
1. View the table structure
desc tableName; show columns from tableName; describe tableName;
The three displayed results are the same, showing filed, type, null, key, default and extra in the table.
--TABLE_SCHEMA indicates the database name select * from information_schema.COLUMNS where TABLE_SCHEMA='gm' and TABLE_NAME='t_role';
The displayed results are more complete.
2. View the table creation statement
show create table tableName;
3. Next, come to a more complete sql, this is all the sql used to synchronize the mysql and orac data dictionaries.
mysql part:
## View all libraries SELECT lower(schema_name) schema_name FROM information_schema.schemata WHERE schema_name NOT IN ( 'mysql', 'information_schema', 'test', 'search', 'tbsearch', 'sbtest', 'dev_ddl' ) ## View all tables in a library SELECT table_name, create_time updated_at, table_type, ENGINE, table_rows num_rows, table_comment, ceil(data_length / 1024 / 1024) store_capacity FROM information_schema.TABLES WHERE table_schema = 'employees' AND table_name NOT LIKE 'tmp#_%' ESCAPE '#' ##View all fields of a table under a library SELECT lower(column_name) column_name, ordinal_position position, column_default dafault_value, substring(is_nullable, 1, 1) nullable, column_type data_type, column_comment, character_maximum_length data_length, numeric_precision data_precision, numeric_scale data_scale FROM information_schema.COLUMNS WHERE table_schema = 'employees' AND table_name = 'employees'; ## View the index of a table under a library SELECT DISTINCT lower(index_name) index_name, lower(index_type) type FROM information_schema.statistics WHERE table_schema = 'employees' AND table_name = 'employees'; ## View an index of a table under a library SELECT lower(column_name) column_name, seq_in_index column_position FROM information_schema.statistics WHERE table_schema = 'employees' AND table_name = 'employees' AND index_name = 'primary'; ## View the comments of a table under a library SELECT table_comment comments FROM information_schema.TABLES WHERE table_schema = 'employees' AND table_name = 'employees'; ## View the comments of a column of a table under a library SELECT lower(column_name) column_name, column_comment comments FROM COLUMNS WHERE table_schema = 'employees' AND table_name = 'employees';
oracle part:
#table structure: SELECT lower(table_name) table_name, TEMPORARY, tablespace_name, num_rows, duration, 'ORACLE' table_type, partitioned, ( SELECT ceil(sum(bytes) / 1024 / 1024) FROM dba_segments b WHERE a. OWNER = b. OWNER AND a.table_name = b.segment_name ) AS store_capacity FROM dba_tables a WHERE OWNER = ? AND table_name NOT LIKE 'TMP%'; SELECT lower(column_name) column_name, column_id position, data_type, data_length, data_precision, data_scale, nullable, data_default default_value, default_length FROM dba_tab_columns WHERE OWNER = ? AND table_name = ?; # index SELECT lower(index_name) index_name, index_type type FROM dba_indexes WHERE OWNER = ? AND table_name = ? AND index_name NOT LIKE 'SYS_IL%'; SELECT lower(column_name) column_name, column_position, descend FROM dba_ind_columns WHERE table_owner = ? AND table_name = ? AND index_name = ?; #collect description SELECT comments FROM dba_tab_comments WHERE OWNER = ? AND table_name = ?; SELECT lower(column_name) column_name, comments FROM dba_col_comments WHERE OWNER = ? AND table_name = ?; #database SELECT lower(username) username FROM dba_users WHERE username NOT IN ( 'STDBYPERF', 'READONLY', 'APPQOSSYS', 'ANYSQL', 'DBFLASH', 'SYS', 'SYSTEM', 'MONITOR', 'TBSEARCH', 'MANAGER', 'SYSMAN', 'EXFSYS', 'WMSYS', 'DIP', 'TSMSYS', 'ORACLE_OCM', 'OUTLN', 'DBSNMP', 'PERFSTAT', 'SEARCH', 'TOOLS', 'TBDUMP', 'DMSYS', 'XDB', 'ANONYMOUS', 'DEV_DDL' ); #segsize SELECT round(sum(bytes) / 1024 / 1024, 0) mbytes FROM dba_segments WHERE OWNER = ? AND segment_name = ?;