RelationIdLoader is not respecting maxAliasLength

[janzipek]

Issue Description

RelationIdLoader class is doing selects, but it's not using DriverUtils.buildAlias so the selects can end up being truncated and all related behaviour is broken. This for example breaks relationLoadStrategy: 'query' when the relation key ends up being too long.

Expected Behavior

RelationIdLoader should use DriverUtils.buildAlias when creating column aliases generating column aliases that fit the maxAliasLength prop of driver.

Actual Behavior

RelationIdLoader ignores maxAliasLength.

Steps to Reproduce

(in postgresql)

Schema

@Entity()
export class SuperLongTableName {
    @PrimaryGeneratedColumn()
    id: number
    
    @Column()
    name: string
    
    @OneToMany(() => SuperLongTableNameWhichIsRelatedToOriginalTable, table => table.superLongTableName)
    relatedToOriginal: SuperLongTableNameWhichIsRelatedToOriginalTable[]
}

@Entity()
export class SuperLongTableNameWhichIsRelatedToOriginalTable{
    @PrimaryGeneratedColumn()
    id: number

    @Column()
    superLongTableNameId: number;
    
    @ManyToOne(() => SuperLongTableName, table => table.relatedToOriginal)
    @JoinColumn({ name: 'superLongTableNameId' })
    superLongTableName: SuperLongTableName
}

INSERT INTO "SuperLongTableName" ("name") VALUES ('test');
INSERT INTO "SuperLongTableNameWhichIsRelatedToOriginal" ("superLongTableNameId") VALUES (1);

const data = await appDataSource.getRepository(SuperLongTableName).findOne({
  where: { id: 1 },
  relations: { relatedToOriginal: true }
})

// data = { name: 'test', relatedToOriginal: [] }

This is because RelationIdLoader will generate column with name: SuperLongTableNameWhichIsRelatedToOriginal_relatedToOriginal_superLongTableNameId which is then truncated by database and all the conditions in the code fail because of that.

Relevant issues

#3118

My Environment

Dependency	Version
Operating System
Node.js version	14.19.1
Typescript version	4.8.2
TypeORM version	0.3.7

Relevant Database Driver(s)

DB Type	Reproducible
aurora-mysql	no
aurora-postgres	no
better-sqlite3	no
cockroachdb	no
cordova	no
expo	no
mongodb	no
mysql	no
nativescript	no
oracle	no
postgres	yes
react-native	no
sap	no
spanner	no
sqlite	no
sqlite-abstract	no
sqljs	no
sqlserver	no

Are you willing to resolve this issue by submitting a Pull Request?

• ✖️ Yes, I have the time, and I know how to start.
• ✅ Yes, I have the time, but I don't know how to start. I would need guidance.
• ✖️ No, I don’t have the time, but I can support (using donations) development.
• ✖️ No, I don’t have the time and I’m okay to wait for the community / maintainers to resolve this issue.

(EDIT: Fixed the example, the names were too short)

[depyronick]

I'm having propertyPath undefined error while using query relations. Is this related to that? Works with join but not with query. Mysql

[depyronick]

ok... it's because inverse side reference should be different than the referencedColumnName in my case

[depyronick]

but seriously, any chance this should cause problems?