When I create table, MySQL changes everything except row names.
Example:
CREATE TABLE MY_TABLE
(
table_id int NOT NULL AUTO_INCREMENT,
PRIMARY KEY(table_id),
table_1 varchar(45),
table_2 varchar(45),
table_3 varchar(999),
table_4 varchar(45)
)"
MySQL sets everything primary except table_id and sets everything unique, index and full text.
If I make my custom table everything goes on random mode. Something is primary, something unique.
I'm on shared hosting on asmallorange.com.
CREATE TABLE `MY_TABLE` ( `table_id` int(11) NOT NULL AUTO_INCREMENT, `table_1` varchar(45) DEFAULT NULL, `table_2` varchar(45) DEFAULT NULL, `table_3` varchar(999) DEFAULT NULL, `table_4` varchar(45) DEFAULT NULL, PRIMARY KEY (`table_id`)) ENGINE=MyISAM DEFAULT CHARSET=latin1
Here is SHOW CREATE TABLE MY_TABLE
I'm using phpAdmin 3.5.5.
CREATE TABLE `my_table` (
`table_id` int(10) NOT NULL AUTO_INCREMENT,
`title` varchar(100) COLLATE utf8_unicode_ci NOT NULL,
`content` longtext COLLATE utf8_unicode_ci NOT NULL,
`created_at` datetime NOT NULL,
PRIMARY KEY (`table_id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
Here is an example of creating table with different fields.
Related
newbie and appreciate your help.
So I have the below employee table with emp_id as primary and auto incremental. I would like to avoid users from inserting new record when the combination of first_name and last_name already exists.
I am connecting the DB to windows from (VB.net), ultimately I would like to display a message saying that the user's first and last name already exists. I could do it progrmaticly by vb code, however i am wondering if I can setup this check at the database level.
CREATE TABLE `employee` (
`emp_id` smallint(5) unsigned NOT NULL AUTO_INCREMENT,
`first_name` varchar(20) NOT NULL,
`middle_name` varchar(30) DEFAULT NULL,
`last_name` varchar(20) NOT NULL,
`date_of_birth` varchar(45) NOT NULL,
`gender` char(6) NOT NULL,
PRIMARY KEY (`emp_id'),
UNIQUE KEY `employee_id_UNIQUE` (`emp_id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8
You can make constraints on sets of columns like this:
CREATE TABLE `employee` (
`emp_id` smallint(5) unsigned NOT NULL AUTO_INCREMENT,
`first_name` varchar(20) NOT NULL,
`middle_name` varchar(30) DEFAULT NULL,
`last_name` varchar(20) NOT NULL,
`date_of_birth` varchar(45) NOT NULL,
`gender` char(6) NOT NULL,
PRIMARY KEY (`emp_id'),
UNIQUE KEY `employee_name_UNIQUE` (`first_name`, `last_name`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8
That means if the combination of first_name and last_name already exists in the database, if you try to insert a new row with the same values, it results in a duplicate key error.
You need to write code in your application to handle that error, and then display an appropriately helpful message to the user.
I have a strange problem in which I'm not able to delete a table as a foreign key constraint fails. The scenario is as follows.
I'm trying to drop the table departments from my DB, the structure for which is as follows:
show create table `departments`
CREATE TABLE `departments` (
`dept_id` int(11) NOT NULL AUTO_INCREMENT,
`dept_name` varchar(50) NOT NULL,
PRIMARY KEY (`dept_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
Now, the only other table in the database that has department_id is the employee table:
show create table employee
CREATE TABLE `employee` (
`emp_id` varchar(20) NOT NULL,
`role` varchar(10) DEFAULT NULL,
`password` varchar(500) DEFAULT NULL,
`division_id` int(20) DEFAULT NULL,
`email_bb` varchar(100) DEFAULT NULL,
`is_active` tinyint(1) NOT NULL,
`date_joining` date DEFAULT NULL,
`date_confirmation` date DEFAULT NULL,
`date_appraisal` date DEFAULT NULL,
`date_leaving` date DEFAULT NULL,
`first_name` varchar(100) DEFAULT NULL,
`middle_name` varchar(100) DEFAULT NULL,
`last_name` varchar(100) DEFAULT NULL,
`sex` varchar(1) DEFAULT NULL,
`dob` date DEFAULT NULL,
`email_other` varchar(100) DEFAULT NULL,
`contact` varchar(100) DEFAULT NULL,
`present_addr` varchar(1000) DEFAULT NULL,
`perma_addr` varchar(1000) DEFAULT NULL,
PRIMARY KEY (`emp_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
As you can see, none of these tables are related via foreign keys. So why do I get this error when trying to drop the department table:
#1217 - Cannot delete or update a parent row: a foreign key constraint fails
Is there a better way (and hopefully, simpler) way to see the foreign keys defined? What might be going wrong?
show create table doesn't show incoming FK restraints (e.g. FK is specified in child table, not parent)
So there is a possibility that you have another table with a FK constraint to that table. I usually dump the schema of the database, which shows all FK constraints.
I am working on magento platform.I face a problem regarding values insertion to specific field: My query run perfect but one specific column not working for any query.I try my best but didn't find why .When i change the column type from int to varchar type it works.This is my table structure.
CREATE TABLE `followupemails_emaillogs` (
`id` int(8) NOT NULL AUTO_INCREMENT,
`schedule_time` datetime DEFAULT NULL,
`sent_time` datetime DEFAULT NULL,
`email_status` varchar(100) DEFAULT NULL,
`client_name` varchar(250) DEFAULT NULL,
`client_email` varchar(250) DEFAULT NULL,
`followupemails_id` int(11) DEFAULT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=30 DEFAULT CHARSET=latin1.
the "followupemails_id" column not working in insert and update query.This is one update query where record exist that id(29). UPDATE followupemails_emaillogs SET followupemails_id=5 WHERE id =29.
This is insertion query INSERT INTO followupemails_emaillogs SET followupemails_id=4, schedule_time='2013-10-23 08:10:00', email_status='pending', client_name='ayaz ali'.this works fine on fiddle but not on my sqlyog ? what could be the issue.At last i find query that work perfect
.INSERT INTO followupemails_emaillogs (followupemails_id,schedule_time,email_status,client_name,client_email) VALUES (26,'2013-10-23 08:10:00','pending','ayaz ali','mamhmood#yahoo.com');
Can anyone tell me why set query not working but second query works perfect.so that i can accept his answer.Thanks for all your help
Try like this
To Create,
CREATE TABLE followupemails_emaillogs (
id int(8) NOT NULL AUTO_INCREMENT PRIMARY KEY,
schedule_time datetime DEFAULT NULL,
sent_time datetime DEFAULT NULL,
email_status varchar(100) DEFAULT NULL,
client_name varchar(250) DEFAULT NULL,
client_email varchar(250) DEFAULT NULL,
followupemails_i int(11) DEFAULT NULL,
UNIQUE (id)
)
To Insert,
INSERT INTO followupemails_emaillogs (schedule_time,sent_time,email_status,client_name,client_email,followupemails_i)
VALUES
('2012-05-05','2012-05-06',"sent","sagar","sagar#xxxx.com",2)
the whole query is ok
CREATE TABLE `followupemails_emaillogs` (
`id` int NOT NULL AUTO_INCREMENT,
`schedule_time` datetime DEFAULT NULL,
`sent_time` datetime DEFAULT NULL,
`email_status` varchar(100) DEFAULT NULL,
`client_name` varchar(250) DEFAULT NULL,
`client_email` varchar(250) DEFAULT NULL,
`followupemails_id` int DEFAULT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=30 DEFAULT CHARSET=latin1.
but at the last there is dot which is actually error so remove the dot and create the table
latin1.
so remove the dot sign and not null in id filed use this line by default fields are null so don't use default null
id int (8) AUTO_INCREMENT
CREATE TABLE `followupemails_emaillogs` (
`id` int (8) AUTO_INCREMENT,
`schedule_time` datetime DEFAULT NULL,
`sent_time` datetime DEFAULT NULL,
`email_status` varchar(100),
`client_name` varchar(250),
`client_email` varchar(250),
`followupemails_id` int,
PRIMARY KEY (`id`),
UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=30 DEFAULT CHARSET=latin1
don't need (11) in the sql query for int operator , This get for length of the nvarchar,varchar datatype column only not a int datatype,So change and write int instead of int(11) and int(8)
Try this query instead of your query
CREATE TABLE `followupemails_emaillogs` (
`id` int NOT NULL AUTO_INCREMENT,
`schedule_time` datetime DEFAULT NULL,
`sent_time` datetime DEFAULT NULL,
`email_status` varchar(100) DEFAULT NULL,
`client_name` varchar(250) DEFAULT NULL,
`client_email` varchar(250) DEFAULT NULL,
`followupemails_id` int DEFAULT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=30 DEFAULT CHARSET=latin1.
I have 3 tables in which I'm trying to preform joins on, and inserting the resulting data into another table. The query is taking anywhere between 15-30 mins depending on the dataset. The tables I'm selecting from and joining on are at least 25k records each but will quickly grow to be 500k+.
I tried adding indexes on the fields but still isn't helping that much. Are there any other things I can try or are joins on this scale just going to take this long?
Here is the query I'm trying to perform:
INSERT INTO audience.topitem
(runs_id, total_training_count, item, standard_index_value, significance, seed_count, nonseed_count, prod, model_type, level_1, level_2, level_3, level_4, level_5)
SELECT 5, seed_count + nonseed_count AS total_training_count,
ii.item, standard_index_value, NULL, seed_count, nonseed_count,
standard_index_value * seed_count AS prod, 'site', topic_L1, topic_L2, topic_L3, topic_L4, topic_L5
FROM audience.item_indexes ii
LEFT JOIN audience.usercounts uc ON ii.item = uc.item AND ii.runs_id = uc.runs_id
LEFT JOIN categorization.categorization at on ii.item = at.url
WHERE ii.runs_id = 5
Table: audience.item_indexes
CREATE TABLE `item_indexes` (
`item` varchar(1024) DEFAULT NULL,
`standard_index_value` float DEFAULT NULL,
`runs_id` int(11) DEFAULT NULL,
`model_type` enum('site','term','combo') DEFAULT NULL,
KEY `item_idx` (`item`(333))
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
Table: audience.usercounts
CREATE TABLE `usercounts` (
`item` varchar(1024) DEFAULT NULL,
`seed_count` int(11) DEFAULT NULL,
`nonseed_count` int(11) DEFAULT NULL,
`significance` float(19,6) DEFAULT NULL,
`runs_id` int(11) DEFAULT NULL,
`model_type` enum('site','term','combo') DEFAULT NULL,
KEY `item_idx` (`item`(333))
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
Table: audience.topitem
CREATE TABLE `topitem` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`total_training_count` int(11) DEFAULT NULL,
`item` varchar(1024) DEFAULT NULL,
`standard_index_value` float(19,6) DEFAULT NULL,
`significance` float(19,6) DEFAULT NULL,
`seed_count` int(11) DEFAULT NULL,
`nonseed_count` int(11) DEFAULT NULL,
`prod` float(19,6) DEFAULT NULL,
`cat_type` varchar(32) DEFAULT NULL,
`cat_level` int(11) DEFAULT NULL,
`conf` decimal(19,9) DEFAULT NULL,
`level_1` varchar(64) DEFAULT NULL,
`level_2` varchar(64) DEFAULT NULL,
`level_3` varchar(64) DEFAULT NULL,
`level_4` varchar(64) DEFAULT NULL,
`level_5` varchar(64) DEFAULT NULL,
`runs_id` int(11) DEFAULT NULL,
`model_type` enum('site','term','combo') DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=825 DEFAULT CHARSET=utf8;
Table: categorization.categorization
CREATE TABLE `AT_categorization` (
`url` varchar(760) NOT NULL ,
`language` varchar(10) DEFAULT NULL,
`category` text,
`entity` text,
`source` varchar(255) DEFAULT NULL,
`topic_L1` varchar(45) NOT NULL DEFAULT '',
`topic_L2` varchar(45) NOT NULL DEFAULT '',
`topic_L3` varchar(45) NOT NULL DEFAULT '',
`topic_L4` varchar(45) NOT NULL DEFAULT '',
`topic_L5` varchar(45) NOT NULL DEFAULT '',
`last_refreshed` datetime DEFAULT NULL,
PRIMARY KEY (`url`,`topic_L1`,`topic_L2`,`topic_L3`,`topic_L4`,`topic_L5`),
UNIQUE KEY `inx_url` (`url`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
If you add the following indexes, your query will run faster:
CREATE INDEX runs_idx ON audience.item_indexes (runs_id);
ALTER TABLE audience.usercounts
DROP INDEX item_idx,
ADD INDEX item_idx (runs_id, item(333));
Also, item_indexes is utf8, but AT_categorization is latin1, which keeps any indexes from being used. To address this issue, change AT_categorization to utf8:
ALTER TABLE AT_categorization CHARSET=utf8;
Lastly, for the AT_categorization table, the two indexes
PRIMARY KEY (`url`,`topic_L1`,`topic_L2`,`topic_L3`,`topic_L4`,`topic_L5`),
UNIQUE KEY `inx_url` (`url`)
are redundant. So you could DROP these, and simply have the url field be the primary key:
ALTER TABLE AT_categorization
DROP PRIMARY KEY,
DROP KEY `inx_url`,
ADD PRIMARY KEY (url);
What is the equivalent of MSSQL IDENTITY Columns in MySQL? How would I create this table in MySQL?
CREATE TABLE Lookups.Gender
(
GenderID INT IDENTITY(1,1) NOT NULL,
GenderName VARCHAR(32) NOT NULL
);
CREATE TABLE Lookups.Gender
(
GenderID INT NOT NULL AUTO_INCREMENT,
GenderName VARCHAR(32) NOT NULL
);
CREATE TABLE `Persons` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`LastName` varchar(255) NOT NULL,
`FirstName` varchar(255) DEFAULT NULL,
`Address` varchar(255) DEFAULT NULL,
`City` varchar(255) DEFAULT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=100 DEFAULT CHARSET=latin1;
This above example uses the AUTO_INCREMENT syntax. You can specify a starting offset specific to the table.
The Increment, however, has to be set globally.
SET ##auto_increment_increment=10;
You can also set a global default for the offset like follows:
SET ##auto_increment_offset=5;
To view your current values, type SHOW VARIABLES LIKE 'auto_inc%';