octoleo/gh-ost
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

counting child vs parent sie foreign keys on table,

Browse Source 
parent-side foreign keys cannot be discarded
This commit is contained in:
Shlomi Noach 2016-10-10 12:28:56 +02:00
parent 56e0833389
commit a4d566e71c
1 changed files with 24 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
go/logic/inspect.go
View File

@ -63,7 +63,7 @@ func (this *Inspector) ValidateOriginalTable() (err error) {
if err := this.validateTable(); err != nil {
return err
}
if err := this.validateTableForeignKeys(); err != nil {
if err := this.validateTableForeignKeys(this.migrationContext.DiscardForeignKeys); err != nil {
return err
}
if err := this.validateTableTriggers(); err != nil {
@ -349,9 +349,11 @@ func (this *Inspector) validateTable() error {
}
// validateTableForeignKeys makes sure no foreign keys exist on the migrated table
func (this *Inspector) validateTableForeignKeys() error {
func (this *Inspector) validateTableForeignKeys(allowChildForeignKeys bool) error {
query := `
SELECT TABLE_SCHEMA, TABLE_NAME
SELECT
SUM(REFERENCED_TABLE_NAME IS NOT NULL AND TABLE_SCHEMA=? AND TABLE_NAME=?) as num_child_side_fk,
SUM(REFERENCED_TABLE_NAME IS NOT NULL AND REFERENCED_TABLE_SCHEMA=? AND REFERENCED_TABLE_NAME=?) as num_parent_side_fk
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_NAME IS NOT NULL
@ -359,31 +361,37 @@ func (this *Inspector) validateTableForeignKeys() error {
OR (REFERENCED_TABLE_SCHEMA=? AND REFERENCED_TABLE_NAME=?)
)
`
numForeignKeys := 0
err := sqlutils.QueryRowsMap(this.db, query, func(rowMap sqlutils.RowMap) error {
fkSchema := rowMap.GetString("TABLE_SCHEMA")
fkTable := rowMap.GetString("TABLE_NAME")
log.Infof("Found foreign key on %s.%s related to %s.%s", sql.EscapeName(fkSchema), sql.EscapeName(fkTable), sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
numForeignKeys++
numParentForeignKeys := 0
numChildForeignKeys := 0
err := sqlutils.QueryRowsMap(this.db, query, func(m sqlutils.RowMap) error {
numChildForeignKeys = m.GetInt("num_child_side_fk")
numParentForeignKeys = m.GetInt("num_parent_side_fk")
return nil
},
this.migrationContext.DatabaseName,
this.migrationContext.OriginalTableName,
this.migrationContext.DatabaseName,
this.migrationContext.OriginalTableName,
this.migrationContext.DatabaseName,
this.migrationContext.OriginalTableName,
this.migrationContext.DatabaseName,
this.migrationContext.OriginalTableName,
)
if err != nil {
return err
}
if numForeignKeys == 0 {
log.Debugf("Validated no foreign keys exist on table")
return nil
if numParentForeignKeys > 0 {
return log.Errorf("Found %d parent-side foreign keys on %s.%s. Parent-side foreign keys are not supported. Bailing out", numParentForeignKeys, sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
}
if this.migrationContext.DiscardForeignKeys {
log.Debugf("Foreign keys found and will be dropped, as per given --discard-foreign-keys flag")
return nil
if numChildForeignKeys > 0 {
if allowChildForeignKeys {
log.Debugf("Foreign keys found and will be dropped, as per given --discard-foreign-keys flag")
return nil
}
return log.Errorf("Found %d child-side foreign keys on %s.%s. Child-side foreign keys are not supported. Bailing out", numChildForeignKeys, sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
}
return log.Errorf("Found %d foreign keys related to %s.%s. Foreign keys are not supported. Bailing out", numForeignKeys, sql.EscapeName(this.migrationContext.DatabaseName), sql.EscapeName(this.migrationContext.OriginalTableName))
log.Debugf("Validated no foreign keys exist on table")
return nil
}
// validateTableTriggers makes sure no triggers exist on the migrated table