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mirror of https://github.com/uptrace/go-clickhouse.git synced 2025-06-08 23:26:11 +02:00
2022-11-03 11:58:19 +02:00

166 lines
3.3 KiB
Go

package chschema
import (
"strings"
"github.com/uptrace/go-clickhouse/ch/internal"
)
type QueryAppender interface {
AppendQuery(fmter Formatter, b []byte) ([]byte, error)
}
type ColumnsAppender interface {
AppendColumns(fmter Formatter, b []byte) ([]byte, error)
}
//------------------------------------------------------------------------------
// Safe represents a safe SQL query.
type Safe string
var _ QueryAppender = (*Safe)(nil)
func (s Safe) AppendQuery(fmter Formatter, b []byte) ([]byte, error) {
return append(b, s...), nil
}
//------------------------------------------------------------------------------
// FQN represents a fully qualified SQL name, for example, table or column name.
type FQN string
var _ QueryAppender = (*FQN)(nil)
func (s FQN) AppendQuery(fmter Formatter, b []byte) ([]byte, error) {
return fmter.AppendIdent(b, string(s)), nil
}
func AppendFQN(b []byte, field string) []byte {
return appendFQN(b, internal.Bytes(field))
}
func appendFQN(b, src []byte) []byte {
const quote = '"'
var quoted bool
loop:
for _, c := range src {
switch c {
case '*':
if !quoted {
b = append(b, '*')
continue loop
}
case '.':
if quoted {
b = append(b, quote)
quoted = false
}
b = append(b, '.')
continue loop
}
if !quoted {
b = append(b, quote)
quoted = true
}
if c == quote {
b = append(b, quote, quote)
} else {
b = append(b, c)
}
}
if quoted {
b = append(b, quote)
}
return b
}
// Ident represents a SQL identifier, for example, table or column name.
type Ident string
var _ QueryAppender = (*Ident)(nil)
func (s Ident) AppendQuery(fmter Formatter, b []byte) ([]byte, error) {
return fmter.AppendIdent(b, string(s)), nil
}
func AppendIdent(b []byte, field string) []byte {
return appendIdent(b, internal.Bytes(field))
}
func appendIdent(b, src []byte) []byte {
const quote = '"'
b = append(b, quote)
for _, c := range src {
if c == quote {
b = append(b, quote, quote)
} else {
b = append(b, c)
}
}
b = append(b, quote)
return b
}
//------------------------------------------------------------------------------
type QueryWithArgs struct {
Query string
Args []any
}
var _ QueryAppender = (*QueryWithArgs)(nil)
func SafeQuery(query string, args []any) QueryWithArgs {
if args == nil {
args = make([]any, 0)
} else if len(query) > 0 && strings.IndexByte(query, '?') == -1 {
internal.Warn.Printf("query %q has %v args, but no placeholders", query, args)
}
return QueryWithArgs{
Query: query,
Args: args,
}
}
func UnsafeIdent(ident string) QueryWithArgs {
return QueryWithArgs{Query: ident}
}
func (q QueryWithArgs) IsZero() bool {
return q.Query == "" && q.Args == nil
}
func (q QueryWithArgs) IsEmpty() bool {
return q.Query == ""
}
func (q QueryWithArgs) AppendQuery(fmter Formatter, b []byte) ([]byte, error) {
if q.Args == nil {
return fmter.AppendIdent(b, q.Query), nil
}
return fmter.AppendQuery(b, q.Query, q.Args...), nil
}
func (q QueryWithArgs) Value() Safe {
b, _ := q.AppendQuery(emptyFmter, nil)
return Safe(b)
}
//------------------------------------------------------------------------------
type QueryWithSep struct {
QueryWithArgs
Sep string
}
func SafeQueryWithSep(query string, args []any, sep string) QueryWithSep {
return QueryWithSep{
QueryWithArgs: SafeQuery(query, args),
Sep: sep,
}
}