In mysql, you can query "information_schema.TABLES" information through the "SELECT" statement to obtain the metadata information of the data table in the specified database, and use the "COUNT(*)" function to count the number of metadata to calculate The number of tables in the database.
The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.
In mysql, you can query the "information_schema.TABLES" information through the "SELECT" statement to calculate the number of tables in the database.
Grammar:
SELECT COUNT(*) TABLES, table_schema FROM information_schema.TABLES WHERE table_schema = 'dbname' GROUP BY table_schema;
Example:
SELECT COUNT(*) TABLES, table_schema FROM information_schema.TABLES WHERE table_schema = 'bwlbis' GROUP BY table_schema;
Description:
The tables in the information_schema database are all read-only and cannot be updated, deleted, inserted, etc., nor can triggers be added, because they are actually just a view, not a basic table, and have no associated files.
information_schema.tables
stores the metadata information of the data table. Commonly used fields are introduced below:
table_schema: Record database name ;
table_name: record data table name;
engine: storage engine;
table_rows : A rough row estimate about the table;
data_length : The size of the record table (in bytes);
index_length : The index of the record table The size of 】
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