[Oracle Database] Database object management

Create tables SQL > create table customers (customer_id NUMBER (12), cust_first_name VARCHAR2 (40), cust_last_name VARCHAR2 (40), nls_language VARCHAR2 (3), nls_territory VARCHAR2 (30), credit_limit NUMBER (9 ~ (2)), cust_email VARCHAR2 (100) Account_mgr_id NUMBER (12), customer_since DATE, customer_class VARCHAR (40), suggestions VARCHAR (40), dob DATE, mailshot VARCHAR (1), partner_mailshot VARCHAR (1), preferred_address NUMBER (12) Preferred_card NUMBER (12)) Table created. Import data SQL > exec dbms_stats.gather_schema_stats ('SOE'); PL/SQL procedure successfully completed.SQL > set line 200SQL > select table_name,num_rows,blocks,status,tablespace_name from user_tables TABLE_NAME NUM_ROWS BLOCKS STATUS TABLESPACE_NAME---CUSTOMERS 1000000 16087 VALID SOESQL > col data_type for a15SQL > col nullable for a10SQL > select table_name Column_name,data_type,data_length,nullable from user_tab_columns where table_name = 'CUSTOMERS' TABLE_NAME COLUMN_NAME DATA_TYPE DATA_LENGTH NULLABLE -CUSTOMERS CUSTOMER_ID NUMBER 22 NCUSTOMERS CUST_FIRST_NAME VARCHAR2 40 YCUSTOMERS CUST_LAST_NAME VARCHAR2 40 YCUSTOMERS NLS_LANGUAGE VARCHAR2 3 YCUSTOMERS NLS_TERRITORY VARCHAR2 30 YCUSTOMERS CREDIT_LIMIT NUMBER 22 YCUSTOMERS CUST_EMAIL VARCHAR2 100 YCUSTOMERS ACCOUNT_MGR_ID NUMBER 22 YCUSTOMERS CUSTOMER_SINCE DATE 7 YCUSTOMERS CUSTOMER_CLASS VARCHAR2 40 YCUSTOMERS SUGGESTIONS VARCHAR2 40 YTABLE_NAME COLUMN_NAME DATA_TYPE DATA_LENGTH NULLABLE -CUSTOMERS DOB DATE 7 YCUSTOMERS MAILSHOT VARCHAR2 1 YCUSTOMERS PARTNER_MAILSHOT VARCHAR2 1 YCUSTOMERS PREFERRED_ADDRESS NUMBER 22 YCUSTOMERS PREFERRED_CARD NUMBER 22 Y create index SQL > create unique index customers_pk on customers (customer_id) Index created.SQL > col index_name for a30SQL > col index_type for a15SQL > col table_name for a20SQL > col tablespace_name for a20SQL > select index_name,index_type,table_name,num_rows,distinct_keys,blevel,status,tablespace_name from user_indexes INDEX_NAME INDEX_TYPE TABLE_NAME NUM_ROWS DISTINCT_KEYS BLEVEL STATUS TABLESPACE_NAME-- -- CUSTOMERS_PK NORMAL CUSTOMERS 1000000 1000000 2 VALID SOESQL > col column_name for a30SQL > select index_name Table_name,column_name,column_position from user_ind_columns INDEX_NAME TABLE_NAME COLUMN_NAME COLUMN_POSITION -CUSTOMERS_PK CUSTOMERS CUSTOMER_ID 1 create primary key constraint SQL > alter table customers add constraint customers_pk primary key (customer_id) Table altered.SQL > col constraint_name for a30SQL > col constraint_type for a15SQL > col table_name for a30SQL > col index_name for a30SQL > select constraint_name,constraint_type,table_name,index_name,status from user_constraints where constraint_type ='P' CONSTRAINT_NAME CONSTRAINT_TYPE TABLE_NAME INDEX_NAME STATUS -CUSTOMERS_PK P CUSTOMERS CUSTOMERS_PK ENABLEDSQL > col constraint_name for a30SQL > col table_name for a30SQL > col column_name for a30SQL > select constraint_name Table_name,column_name,position from user_cons_columns CONSTRAINT_NAME TABLE_NAME COLUMN_NAME POSITION -- CUSTOMERS_PK CUSTOMERS CUSTOMER_ID 1