How to Count the Number of Tables in a Database

Database management work often requires statistics in the number of tables in the database, which is very practical in database audit, documentation or maintenance. Most relational database management systems (RDBMS) provide convenient methods to count the number of forms by system directory or information mode. Here are several statistical methods for commonly used databases.

PostgreSQL database

In PostgreSQL, you can use the

view query number of forms in specific mode:

information_schema.tables

<code class="language-sql">SELECT COUNT(*)
FROM information_schema.tables
WHERE table_schema = 'public';</code>

If you need to query other modes, replace

to the target mode name.
• 'public'
mysql database

In mysql, you can also use view and filter according to the database name:

information_schema.tables

Please replace for your database name.

<code class="language-sql">SELECT COUNT(*)
FROM information_schema.tables
WHERE table_schema = 'your_database_name';</code>

• SQL Server database your_database_name

In SQL Server, you can use

Directory view statistics to all the number of tables in the current database:

This query is suitable for the database you currently connected. sys.tables

<code class="language-sql">SELECT COUNT(*)
FROM sys.tables;</code>

Sqlite database

In SQLite, you can use the number of

table statistical forms:

Oracle database

sqlite_master In Oracle database, you can use

view and filter according to the mode owner:

<code class="language-sql">SELECT COUNT(*)
FROM sqlite_master
WHERE type = 'table';</code>

Please replace to the corresponding mode name.

all_tables Summary

<code class="language-sql">SELECT COUNT(*)
FROM all_tables
WHERE owner = 'YOUR_SCHEMA_NAME';</code>

Although the methods of storing metadata in each database system are different, querying the system directory or information mode is a common method for obtaining the table detailed information. With these query statements, you can quickly count the number of tables in any database.
• YOUR_SCHEMA_NAME If you need more detailed help for specific databases, please tell me the database type you use!

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