Using the command:
CREATE TABLE IF NOT EXISTS `test`.`t1` (
`col` VARCHAR(16) NOT NULL
) ENGINE=MEMORY;
Running this twice in the MySQL Query Browser resu开发者_开发技巧lts in:
Table 't1' already exists Error 1050
I would have thought that creating the table "IF NOT EXISTS" would not throw errors. Am I missing something or is this a bug? I am running version 5.1. Thanks.
Works fine for me in 5.0.27
I just get a warning (not an error) that the table exists;
As already stated, it's a warning not an error, but (if like me) you want things to run without warnings, you can disable that warning, then re-enable it again when you're done.
SET sql_notes = 0; -- Temporarily disable the "Table already exists" warning
CREATE TABLE IF NOT EXISTS ...
SET sql_notes = 1; -- And then re-enable the warning again
You can use the following query to create a table to a particular database in MySql.
create database if not exists `test`;
USE `test`;
SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0;
/*Table structure for table `test` */
CREATE TABLE IF NOT EXISTS `tblsample` (
`id` int(11) NOT NULL auto_increment,
`recid` int(11) NOT NULL default '0',
`cvfilename` varchar(250) NOT NULL default '',
`cvpagenumber` int(11) NULL,
`cilineno` int(11) NULL,
`batchname` varchar(100) NOT NULL default '',
`type` varchar(20) NOT NULL default '',
`data` varchar(100) NOT NULL default '',
PRIMARY KEY (`id`)
);
create database if not exists `test`;
USE `test`;
SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0;
/*Table structure for table `test` */
***CREATE TABLE IF NOT EXISTS `tblsample` (
`id` int(11) NOT NULL auto_increment,
`recid` int(11) NOT NULL default '0',
`cvfilename` varchar(250) NOT NULL default '',
`cvpagenumber` int(11) NULL,
`cilineno` int(11) NULL,
`batchname` varchar(100) NOT NULL default '',
`type` varchar(20) NOT NULL default '',
`data` varchar(100) NOT NULL default '',
PRIMARY KEY (`id`)
);***
I have a solution to a problem that may also apply to you. My database was in a state where a DROP TABLE
failed because it couldn't find the table... but a CREATE TABLE
also failed because MySQL thought the table existed. (This state could easily mess with your IF NOT EXISTS clause).
I eventually found this solution:
sudo mysqladmin flush-tables
For me, without the sudo
, I got the following error:
mysqladmin: refresh failed; error: 'Access denied; you need the RELOAD privilege for this operation'
(Running on OS X 10.6)
Create mysql connection with following parameter. "'raise_on_warnings': False". It will ignore the warning. e.g.
config = {'user': 'user','password': 'passwd','host': 'localhost','database': 'db', 'raise_on_warnings': False,}
cnx = mysql.connector.connect(**config)
I had a similar Problem as @CraigWalker on debian: My database was in a state where a DROP TABLE
failed because it couldn't find the table, but a CREATE TABLE
also failed because MySQL thought the table still existed. So the broken table still existed somewhere although it wasn't there when I looked in phpmyadmin.
I created this state by just copying the whole folder that contained a database with some MyISAM
and some InnoDB
tables
cp -a /var/lib/mysql/sometable /var/lib/mysql/test
(this is not recommended!)
All InnoDB tables where not visible in the new database test
in phpmyadmin.
sudo mysqladmin flush-tables
didn't help either.
My solution: I had to delete the new test database with drop database test
and copy it with mysqldump
instead:
mysqldump somedatabase -u username -p -r export.sql
mysql test -u username -p < export.sql
Well there are lot of answeres already provided and lot are making sense too.
Some mentioned it is just warning and some giving a temp way to disable warnings. All that will work but add risk when number of transactions in your DB is high.
I came across similar situation today and here is the query I came up with...
declare
begin
execute immediate '
create table "TBL" ("ID" number not null)';
exception when others then
if SQLCODE = -955 then null; else raise; end if;
end;
/
This is simple, if exception come while running query it will be suppressed. and you can use same for SQL
or Oracle
.
If anyone is getting this error after a Phpmyadmin export, using the custom options and adding the "drop tables" statements cleared this right up.
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