gf/contrib/drivers/clickhouse/clickhouse_table_fields.go
2024-01-30 20:03:58 +08:00

71 lines
1.9 KiB
Go

// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package clickhouse
import (
"context"
"fmt"
"github.com/gogf/gf/v2/database/gdb"
"github.com/gogf/gf/v2/text/gregex"
"github.com/gogf/gf/v2/util/gutil"
)
const (
tableFieldsColumns = `name,position,default_expression,comment,type,is_in_partition_key,is_in_sorting_key,is_in_primary_key,is_in_sampling_key`
)
// TableFields retrieves and returns the fields' information of specified table of current schema.
// Also see DriverMysql.TableFields.
func (d *Driver) TableFields(ctx context.Context, table string, schema ...string) (fields map[string]*gdb.TableField, err error) {
var (
result gdb.Result
link gdb.Link
usedSchema = gutil.GetOrDefaultStr(d.GetSchema(), schema...)
)
if link, err = d.SlaveLink(usedSchema); err != nil {
return nil, err
}
var (
getColumnsSql = fmt.Sprintf(
"select %s from `system`.columns c where `table` = '%s'",
tableFieldsColumns, table,
)
)
result, err = d.DoSelect(ctx, link, getColumnsSql)
if err != nil {
return nil, err
}
fields = make(map[string]*gdb.TableField)
for _, m := range result {
var (
isNull = false
fieldType = m["type"].String()
)
// in clickhouse , field type like is Nullable(int)
fieldsResult, _ := gregex.MatchString(`^Nullable\((.*?)\)`, fieldType)
if len(fieldsResult) == 2 {
isNull = true
fieldType = fieldsResult[1]
}
position := m["position"].Int()
if result[0]["position"].Int() != 0 {
position -= 1
}
fields[m["name"].String()] = &gdb.TableField{
Index: position,
Name: m["name"].String(),
Default: m["default_expression"].Val(),
Comment: m["comment"].String(),
// Key: m["Key"].String(),
Type: fieldType,
Null: isNull,
}
}
return fields, nil
}