Oracle is a commonly used database management system that is often used to store enterprise data. If you want to query the tables under the user in Oracle, you need to perform the following steps:
- Log in to the Oracle database and enter your user name and password.
-
Execute the following SQL statement:
SELECT TABLE_NAME FROM USER_TABLES;
This statement will query the names of all tables under the currently logged in user.
-
If you want to query other users' tables, you can use the following SQL statement:
SELECT TABLE_NAME FROM ALL_TABLES WHERE OWNER = 'username';
where , 'username' refers to the name of the user to be queried. This statement will query the names of all tables under the specified user.
-
If you want to query all tables in the Oracle database, you can use the following SQL statement:
SELECT TABLE_NAME FROM ALL_TABLES;
This statement will Query the names of all tables under all users.
After querying the table name, you can further query the attributes of the table, such as column names, data types, etc. You can use the following SQL statement:
SELECT COLUMN_NAME, DATA_TYPE FROM ALL_TAB_COLUMNS WHERE TABLE_NAME = 'table_name';
Where, 'table_name' refers to the name of the table to be queried. This statement will query all column names and data types of the specified table.
In short, querying the tables under the user in the Oracle database requires using different SQL statements, depending on what needs to be queried. Proficiency in these statements can greatly improve work efficiency in the Oracle database.
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