In some databases like MySQL, you can even specify where to insert the new column using the FIRST or AFTER clauses, though this is not a standard feature. Altering table to add new column(s) ALTER TABLE mytable ADD column DataType OptionalTableConstraint DEFAULT default_value; Removing ...
Most of the rest of this discussion centers on the complex case of a table that is being modified -- any row could be UPDATEd, INSERTs could go anywhere into the table. And it assumes a single machine, or a single Master. Some likely special cases are covered near the end ("Alternative...
Bug #117341Cannot drop index '<unknown key name>' when altering table in any way Submitted:30 Jan 14:16Modified:31 Jan 13:30 Reporter:Tarvo REmail Updates: Status:ClosedImpact on me: None Category:MySQL ServerSeverity:S3 (Non-critical) ...
Description: Hi team, When altering the table default charset and its columns' charsets from utf8mb3 to utf8mb4 in one statement, as described in this document https://dev.mysql.com/doc/refman/8.0/en/charset-unicode-conversion.html, then it takes a while to complete for a table with ~...
Now, if I put a "SELECT * FROM test;" or a "SHOW COLUMNS FROM test;" or a "SHOW TABLE STATUS;" between the CREATE TABLE statements and the ALTER TABLE statements, then the SQL executes without errors. However, a "FLUSH TABLES;" does not prevent the error, as the MySQL documentation...
Learning MySQL and MariaDB by Russell J.T. Dyer Buy on Amazon Buy on ebooks.com Chapter 5. Altering Tables Despite the best planning, you will need occasionally to change the structure or other aspects of your tables. We cannot imagine everything that we might want to do with a table, ...
returns a result indicating this lack of support. You can make OPTIMIZE TABLE work for other storage engines by starting mysqld with the --skip-new option. In this case, OPTIMIZE TABLE is just mapped to ALTER TABLE....
In this case, if the database name is not specified, the main is automatically chosen. sqlite> CREATE TEMPORARY TABLE Cars(Id INTEGER PRIMARY KEY, Name TEXT, Price INTEGER); sqlite> INSERT INTO temp.Cars VALUES (1, 'Kia', 24300); sqlite> .databases main: /home/janbodnar/tmp/test.db ...
By default,OPTIMIZE TABLEdoesnotwork for tables created using any other storage engine and returns a result indicating this lack of support. You can makeOPTIMIZE TABLEwork for other storage engines by startingmysqldwith the--skip-newoption. In this case,OPTIMIZE TABLEis just mapped toALTER TABLE...
I was trying to alter (ALTER TABLE) a MyISAM table on our production system to add several columns. The table is 13 M and some records and about 2.5 GB in size. The platform is W2k3 with MySQL 4.0.20. After well over an hour of processing, the alter query returns: ...