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SELECT * FROM INFORMATION_SCHEMA.ST_GEOMETRY_COLUMNS WHERE SRS_ID=4326; 

SRID values must be in the range of 32-bit unsigned integers, with these restrictions: 

•SRID 0 is a valid SRID but cannot be used with DROP SPATIAL REFERENCE SYSTEM . 

•If the value is in a reserved SRID range, a warning occurs. Reserved ranges are [0, 32767] (reserved by EPSG), [60,000,000, 69,999,999] (reserved by EPSG), and [2,000,000,000, 2,147,483,647] (reserved by MySQL). EPSG stands for the European Petroleum Survey Group. 

•Users should not drop SRSs with SRIDs in the reserved ranges. If system-installed SRSs are dropped, the SRS definitions may be recreated for MySQL upgrades. 

## 13.1.32 DROP TABLE Statement 

DROP [TEMPORARY] TABLE [IF EXISTS] tbl_name  [, tbl_name ] ... [RESTRICT | CASCADE] 

DROP TABLE  removes one or more tables. You must have the DROP  privilege for each table. 

Be careful  with this statement! For each table, it removes the table definition and all table data. If the table is partitioned, the statement removes the table definition, all its partitions, all data stored in those partitions, and all partition definitions associated with the dropped table. 

Dropping a table also drops any triggers for the table. 

DROP TABLE  causes an implicit commit, except when used with the TEMPORARY  keyword. See Section 13.3.3, “Statements That Cause an Implicit Commit” . 

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## Important 

When a table is dropped, privileges granted specifically for the table are not automatically dropped. They must be dropped manually. See Section 13.7.1.6, “GRANT Statement” . 

If any tables named in the argument list do not exist, DROP TABLE  behavior depends on whether the IF EXISTS  clause is given: 

•Without IF EXISTS , the statement fails with an error indicating which nonexisting tables it was unable to drop, and no changes are made. 

•With IF EXISTS , no error occurs for nonexisting tables. The statement drops all named tables that do exist, and generates a NOTE  diagnostic for each nonexistent table. These notes can be displayed with SHOW WARNINGS . See Section 13.7.7.42, “SHOW WARNINGS Statement” . 

IF EXISTS  can also be useful for dropping tables in unusual circumstances under which there is an entry in the data dictionary but no table managed by the storage engine. (For example, if an abnormal server exit occurs after removal of the table from the storage engine but before removal of the data dictionary entry.) 

The TEMPORARY  keyword has the following effects: 

•The statement drops only TEMPORARY  tables. 

•The statement does not cause an implicit commit. 

•No access rights are checked. A TEMPORARY  table is visible only with the session that created it, so no check is necessary. 

