Insert Query Check If Record Exists - If Not, Insert It

Insert query check if record exists - If not, Insert it

You can use below query. Here it will insert the ip_address when it is not present in your table.

INSERT INTO ip_list (ip_addr)
SELECT * FROM (SELECT '192.168.100.1') AS tmp
WHERE NOT EXISTS (
    SELECT ip_addr FROM ip_list WHERE ip_addr='192.168.100.1'
);

MySQL: Insert record if not exists in table

I'm not actually suggesting that you do this, as the UNIQUE index as suggested by Piskvor and others is a far better way to do it, but you can actually do what you were attempting:

CREATE TABLE `table_listnames` (
  `id` int(11) NOT NULL auto_increment,
  `name` varchar(255) NOT NULL,
  `address` varchar(255) NOT NULL,
  `tele` varchar(255) NOT NULL,
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB;

Insert a record:

INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
    SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;

Query OK, 1 row affected (0.00 sec)
Records: 1  Duplicates: 0  Warnings: 0

SELECT * FROM `table_listnames`;

+----+--------+-----------+------+
| id | name   | address   | tele |
+----+--------+-----------+------+
|  1 | Rupert | Somewhere | 022  |
+----+--------+-----------+------+

Try to insert the same record again:

INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
    SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;

Query OK, 0 rows affected (0.00 sec)
Records: 0  Duplicates: 0  Warnings: 0

+----+--------+-----------+------+
| id | name   | address   | tele |
+----+--------+-----------+------+
|  1 | Rupert | Somewhere | 022  |
+----+--------+-----------+------+

Insert a different record:

INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'John', 'Doe', '022') AS tmp
WHERE NOT EXISTS (
    SELECT name FROM table_listnames WHERE name = 'John'
) LIMIT 1;

Query OK, 1 row affected (0.00 sec)
Records: 1  Duplicates: 0  Warnings: 0

SELECT * FROM `table_listnames`;

+----+--------+-----------+------+
| id | name   | address   | tele |
+----+--------+-----------+------+
|  1 | Rupert | Somewhere | 022  |
|  2 | John   | Doe       | 022  |
+----+--------+-----------+------+

And so on...

Update:

To prevent #1060 - Duplicate column name error in case two values may equal, you must name the columns of the inner SELECT:

INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Unknown' AS name, 'Unknown' AS address, '022' AS tele) AS tmp
WHERE NOT EXISTS (
    SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;

Query OK, 1 row affected (0.00 sec)
Records: 1  Duplicates: 0  Warnings: 0

SELECT * FROM `table_listnames`;

+----+---------+-----------+------+
| id | name    | address   | tele |
+----+---------+-----------+------+
|  1 | Rupert  | Somewhere | 022  |
|  2 | John    | Doe       | 022  |
|  3 | Unknown | Unknown   | 022  |
+----+---------+-----------+------+

Check if record exists then insert new row in database table?

I don't know/work-with coldfusion so not sure I'm reading the logic correctly ...

if record does not exist in table1 but
record does exit in contact then
insert a row into inter_work_tbl

The general T-SQL query would look like (note: mixing T-SQL with references to the coldfusion variables):

insert into inter_work_tbl

      (user_id
      ,first_name
      ,last_name
      ,password)

select '#session.user_id#',
       c.fname,
       c.lname,
       '#password#'

from   contact c

where  c.userid = #session.user_id#
and    not exists(select  1
                  from    table1 t
                  where   t.user_id = c.userid)

SQL Server Insert if not exists

instead of below Code

BEGIN
   INSERT INTO EmailsRecebidos (De, Assunto, Data)
   VALUES (@_DE, @_ASSUNTO, @_DATA)
   WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos 
                   WHERE De = @_DE
                   AND Assunto = @_ASSUNTO
                   AND Data = @_DATA);
END

replace with

BEGIN
   IF NOT EXISTS (SELECT * FROM EmailsRecebidos 
                   WHERE De = @_DE
                   AND Assunto = @_ASSUNTO
                   AND Data = @_DATA)
   BEGIN
       INSERT INTO EmailsRecebidos (De, Assunto, Data)
       VALUES (@_DE, @_ASSUNTO, @_DATA)
   END
END

Updated : (thanks to @Marc Durdin for pointing)

Note that under high load, this will still sometimes fail, because a second connection can pass the IF NOT EXISTS test before the first connection executes the INSERT, i.e. a race condition. See stackoverflow.com/a/3791506/1836776 for a good answer on why even wrapping in a transaction doesn't solve this.

How can I do 'insert if not exists' in MySQL?

Use INSERT IGNORE INTO table.

There's also INSERT … ON DUPLICATE KEY UPDATE syntax, and you can find explanations in 13.2.6.2 INSERT ... ON DUPLICATE KEY UPDATE Statement.

Post from bogdan.org.ua according to Google's webcache:

18th October 2007
To start: as of the latest MySQL, syntax presented in the title is not
possible. But there are several very easy ways to accomplish what is
expected using existing functionality.
There are 3 possible solutions: using INSERT IGNORE, REPLACE, or
INSERT … ON DUPLICATE KEY UPDATE.
Imagine we have a table:
CREATE TABLE `transcripts` (
`ensembl_transcript_id` varchar(20) NOT NULL,
`transcript_chrom_start` int(10) unsigned NOT NULL,
`transcript_chrom_end` int(10) unsigned NOT NULL,
PRIMARY KEY (`ensembl_transcript_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
Now imagine that we have an automatic pipeline importing transcripts
meta-data from Ensembl, and that due to various reasons the pipeline
might be broken at any step of execution. Thus, we need to ensure two
things:

repeated executions of the pipeline will not destroy our
> database

repeated executions will not die due to ‘duplicate
> primary key’ errors.
Method 1: using REPLACE
It’s very simple:
REPLACE INTO `transcripts`
SET `ensembl_transcript_id` = 'ENSORGT00000000001',
`transcript_chrom_start` = 12345,
`transcript_chrom_end` = 12678;
If the record exists, it will be overwritten; if it does not yet
exist, it will be created. However, using this method isn’t efficient
for our case: we do not need to overwrite existing records, it’s fine
just to skip them.
Method 2: using INSERT IGNORE Also very simple:
INSERT IGNORE INTO `transcripts`
SET `ensembl_transcript_id` = 'ENSORGT00000000001',
`transcript_chrom_start` = 12345,
`transcript_chrom_end` = 12678;
Here, if the ‘ensembl_transcript_id’ is already present in the
database, it will be silently skipped (ignored). (To be more precise,
here’s a quote from MySQL reference manual: “If you use the IGNORE
keyword, errors that occur while executing the INSERT statement are
treated as warnings instead. For example, without IGNORE, a row that
duplicates an existing UNIQUE index or PRIMARY KEY value in the table
causes a duplicate-key error and the statement is aborted.”.) If the
record doesn’t yet exist, it will be created.
This second method has several potential weaknesses, including
non-abortion of the query in case any other problem occurs (see the
manual). Thus it should be used if previously tested without the
IGNORE keyword.
Method 3: using INSERT … ON DUPLICATE KEY UPDATE:
Third option is to use INSERT … ON DUPLICATE KEY UPDATE
syntax, and in the UPDATE part just do nothing do some meaningless
(empty) operation, like calculating 0+0 (Geoffray suggests doing the
id=id assignment for the MySQL optimization engine to ignore this
operation). Advantage of this method is that it only ignores duplicate
key events, and still aborts on other errors.
As a final notice: this post was inspired by Xaprb. I’d also advise to
consult his other post on writing flexible SQL queries.

SQL check if non-unique record exists—If it does, UPDATE; if not, INSERT the record INTO the table

Because I could not add a unique index/constraint on (post_id, meta_key) (because my database happened to already have duplicate post_id/meta_key rows), here's what ended up working for me.

Hopefully this helps someone in the future, let me know if there's any problems with the solution:

REPLACE INTO wp_postmeta (meta_id, post_id, meta_key, meta_value)
SELECT 
    IFNULL( 
        (SELECT n.meta_id FROM wp_postmeta n 
         WHERE n.meta_key = '_new_column_name' 
         AND n.post_id = o.post_id ), 
        NULL 
    ), 
    o.post_id, '_new_column_name', o.meta_value
FROM wp_postmeta o
WHERE meta_key = '_old_column_name';

If record exists dont insert

You need to change your query a bit, but you can use MySql's DUAL keyword to do this:

string _connStr = @"Data Source = EJQ7FRN; Initial Catalog = BES; Integrated Security = True";
string _query = "INSERT INTO [BES_S] (ISN,Titel,Name) ";
_query = _query + " SELECT @ISN, @Titel, @Name FROM DUAL";
_query = _query + " WHERE NOT EXISTS (SELECT ISN WHERE ISN=@ISN)";

using (SqlConnection conn = new SqlConnection(_connStr))
{
    using (SqlCommand comm = new SqlCommand())
    {
        comm.Connection = conn;
        comm.CommandType = CommandType.Text;
        comm.CommandText = _query;
        comm.Parameters.AddWithValue("@ISN", txtISN.Text);
        comm.Parameters.AddWithValue("@Titel",txtTitel.Text);
        comm.Parameters.AddWithValue("@Name", txtName.Text);
        try
        {
            conn.Open();
            comm.ExecuteNonQuery();
        }
        catch (SqlException ex)
        {

        }
    }
}

DUAL is like a dummy table that you can use to SELECT from.

Insert Query Check If Record Exists - If Not, Insert It