Database

Schatak wrote:

Although worked with SQL server from past 5 years. but now thinking to use MongoDB.

dili1234 wrote:

how many "2007" data are in the table when inserting new record

dili1234 wrote:

CREATE TRIGGER No_of_Publisher_year Before Insert

CREATE TABLE IF NOT EXISTS `tbl_sample`
(
  `tbl_sample_id` INT UNSIGNED NOT NULL,
  `tracked_id` INT UNSIGNED NOT NULL,
  -- other columns goes here,
  PRIMARY KEY (`tbl_sample_id`, `tracked_id`)
)ENGINE = MyISAM

Gilbert Consellado wrote:

But why MySQL accept this query

Gilbert Consellado wrote:

what are you referring about "design-error"?

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

CREATE TABLE IF NOT EXISTS `tbl_sample`
(
  `tbl_sample_id` INT UNSIGNED NOT NULL,
  `tracked_id` INT UNSIGNED NOT NULL,
  -- other columns goes here,
  PRIMARY KEY (`tbl_sample_id`, `tracked_id`)
)ENGINE = MyISAM

CREATE TABLE IF NOT EXISTS `tbl_sample`
(
  `tbl_sample_id` INT UNSIGNED NOT NULL,
  `tracked_id` INT UNSIGNED NOT NULL,
  -- other columns goes here,
  PRIMARY KEY (`tbl_sample_id`),
  INDEX `track` (`track_id` ASC)
)ENGINE = MyISAM

• Personally I would define any column combinations that are unique in real world as unique, natural keys, not as primary keys.
• Beyond that I would define a single columns surrogate key for all tables and always fetch/modify rows based on this surrogate key.