我有两个共享多对多关系的表，即重叠群和路径。
mysql> describe contig ;
+-------------------+----------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+----------------------+------+-----+---------+-------+
| id_contig | smallint(5) unsigned | NO | PRI | NULL | |
| length | smallint(5) unsigned | NO | | NULL | |
| total_rc | int(11) | NO | | NULL | |
| rc_es1 | smallint(6) | NO | | NULL | |
| rc_es2 | smallint(6) | NO | | NULL | |
| rc_ls1 | smallint(6) | NO | | NULL | |
| rc_ls2 | smallint(6) | NO | | NULL | |
| rpkm_es1 | float(10,2) | NO | | NULL | |
| rpkm_es2 | float(10,2) | NO | | NULL | |
| rpkm_ls1 | float(10,2) | NO | | NULL | |
| rpkm_ls2 | float(10,2) | NO | | NULL | |
| hit_id_nr | varchar(50) | YES | | NULL | |
| hit_id_tair | varchar(50) | YES | | NULL | |
| hit_id_uniprot | varchar(50) | YES | | NULL | |
| hit_desc_nr | text | YES | | NULL | |
| hit_desc_tair | text | YES | | NULL | |
| hit_desc_uniprot | text | YES | | NULL | |
| bayseq_likelihood | float(11,9) | YES | | NULL | |
| bayseq_fdr | float(11,9) | YES | | NULL | |
| deseq_fc | float(10,2) | YES | | NULL | |
| deseq_log2fc | float(10,2) | YES | | NULL | |
| deseq_pval | double | YES | | NULL | |
| deseq_padj | double | YES | | NULL | |
| edger_logconc | double | YES | | NULL | |
| edger_log2fc | double | YES | | NULL | |
| edger_pval | double | YES | | NULL | |
| edger_fdr | double | YES | | NULL | |
+-------------------+----------------------+------+-----+---------+-------+
和
mysql> describe path ;
+-----------+----------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+----------------------+------+-----+---------+-------+
| id_path | tinyint(3) unsigned | NO | PRI | NULL | |
| path_name | text | NO | | NULL | |
| path_nseq | smallint(5) unsigned | NO | | NULL | |
| path_map | varchar(8) | NO | | NULL | |
| path_pix | varchar(28) | NO | | NULL | |
+-----------+----------------------+------+-----+---------+-------+
为了链接它们，我创建了一个“交叉表”，即 contig2path ：
mysql> describe contig2path ;
+-----------+----------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+----------------------+------+-----+---------+-------+
| id_contig | smallint(5) unsigned | NO | PRI | NULL | |
| id_path | tinyint(3) unsigned | NO | PRI | NULL | |
+-----------+----------------------+------+-----+---------+-------+
正如您可能想象的那样，我想使用 contig2path 链接表格重叠群和路径中的数据。但在使用任何JOIN之前，我必须使用外键链接表。
-> contig.id_contig would be linked to conti2path.id_contig
-> path.id_path would be linked to contig2path.id_path
我的问题是：如何让主键成为外键？
编辑：您可以使用表格的创建方式：
contig：
CREATE DATABASE IF NOT EXISTS `nutsedge` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ;
USE `nutsedge` ;
-- -----------------------------------------------------
-- Table `nutsedge`.`contig`
-- -----------------------------------------------------
DROP TABLE IF EXISTS `nutsedge`.`contig` ;
CREATE TABLE IF NOT EXISTS `nutsedge`.`contig` (
`id_contig` SMALLINT UNSIGNED NOT NULL ,
`length` SMALLINT UNSIGNED NOT NULL ,
`total_rc` INT NOT NULL ,
`rc_es1` SMALLINT NOT NULL ,
`rc_es2` SMALLINT NOT NULL ,
`rc_ls1` SMALLINT NOT NULL ,
`rc_ls2` SMALLINT NOT NULL ,
`rpkm_es1` FLOAT (10,2) NOT NULL ,
`rpkm_es2` FLOAT (10,2) NOT NULL ,
`rpkm_ls1` FLOAT (10,2) NOT NULL ,
`rpkm_ls2` FLOAT (10,2) NOT NULL ,
`hit_id_nr` VARCHAR(50) NULL ,
`hit_id_tair` VARCHAR(50) NULL ,
`hit_id_uniprot` VARCHAR(50) NULL ,
`hit_desc_nr` TEXT NULL ,
`hit_desc_tair` TEXT NULL ,
`hit_desc_uniprot` TEXT NULL ,
`bayseq_likelihood` FLOAT (11,9) NULL ,
`bayseq_fdr` FLOAT (11,9) NULL ,
`deseq_fc` FLOAT (10,2) NULL ,
`deseq_log2fc` FLOAT (10,2) NULL,
`deseq_pval` DOUBLE NULL,
`deseq_padj` DOUBLE NULL,
`edger_logconc` DOUBLE NULL,
`edger_log2fc` DOUBLE NULL,
`edger_pval` DOUBLE NULL,
`edger_fdr` DOUBLE NULL,
PRIMARY KEY (`id_contig`) )
ENGINE = InnoDB;
SELECT 'NUTSEDGE DATABASE CREATED';
SHOW warnings;
路径：
-- -----------------------------------------------------
-- Table `nutsedge`.`path`
-- -----------------------------------------------------
DROP TABLE IF EXISTS `nutsedge`.`path` ;
CREATE TABLE IF NOT EXISTS `nutsedge`.`path` (
`id_path` TINYINT UNSIGNED NOT NULL ,
`path_name` TEXT NOT NULL ,
`path_nseq` SMALLINT UNSIGNED NOT NULL ,
`path_map` VARCHAR(8) NOT NULL,
`path_pix` VARCHAR(28) NOT NULL,
PRIMARY KEY (`id_path`) )
ENGINE = InnoDB;
SELECT 'PATHWAY TABLE CREATED';
SHOW warnings;
contig2path：
-- -----------------------------------------------------
-- Table `nutsedge`.`contig2path`
-- -----------------------------------------------------
DROP TABLE IF EXISTS `nutsedge`.`contig2path` ;
CREATE TABLE IF NOT EXISTS `nutsedge`.`contig2path` (
`id_contig` SMALLINT UNSIGNED NOT NULL ,
`id_path` TINYINT UNSIGNED NOT NULL ,
PRIMARY KEY (`id_contig`,`id_path`) )
ENGINE = InnoDB;
SELECT 'CONTIG2PATHWAY TABLE CREATED';
SHOW warnings;
答案 0 :(得分：0)
您可以尝试这样的事情： -
Add FOREIGN KEY (id_contig ) REFERENCES conti2path(id_contig)
答案 1 :(得分：0)
创建外键： 您需要分别从contig2path到contig和path的两个引用。 您可以这样创建这些键：
ALTER TABLE contig2path ADD CONSTRAINT fkey1 FOREIGN KEY id_contig REFERENCES contig (id_contig);
ALTER TABLE contig2path ADD CONSTRAINT fkey2 FOREIGN KEY id_path REFERENCES path (id_path);
要在contig2path中创建主键，您可以在创建表时执行以下操作：
create table contig2path (
...,
PRIMARY KEY (id_contig, id_path)
)