// Invariant: only called when len(fragments) > 0
func writeWhereFragmentsToSql(buf common.BufferWriter, fragments []*whereFragment, args *[]interface{}, pos *int64) {
hasConditions := false
for _, f := range fragments {
if f.Condition != "" {
if hasConditions {
buf.WriteString(" AND (")
} else {
buf.WriteRune('(')
hasConditions = true
}
if len(f.Values) > 0 {
// map relative $1, $2 placeholders to absolute
replaced := remapPlaceholders(buf, f.Condition, *pos)
*pos += replaced
*args = append(*args, f.Values...)
} else {
buf.WriteString(f.Condition)
}
buf.WriteRune(')')
} else if f.EqualityMap != nil {
hasConditions = writeEqualityMapToSql(buf, f.EqualityMap, args, hasConditions, pos)
} else {
panic("invalid equality map")
}
}
}
func writeUint64(buf common.BufferWriter, n uint64) {
if n < maxLookup {
buf.WriteString(itoaTab[int(n)])
} else {
buf.WriteString(strconv.FormatUint(n, 10))
}
}
func writePlaceholder64(buf common.BufferWriter, pos int64) {
if pos < maxLookup {
buf.WriteString(placeholderTab[pos])
} else {
buf.WriteRune('$')
buf.WriteString(strconv.FormatInt(pos, 10))
}
}
func writePlaceholder(buf common.BufferWriter, pos int) {
if pos < maxLookup {
buf.WriteString(placeholderTab[pos])
} else {
buf.WriteRune('$')
buf.WriteString(strconv.Itoa(pos))
}
}
// Invariant: for scope conditions only
func writeScopeCondition(buf common.BufferWriter, f *whereFragment, args *[]interface{}, pos *int64) {
buf.WriteRune(' ')
if len(f.Values) > 0 {
// map relative $1, $2 placeholders to absolute
replaced := remapPlaceholders(buf, f.Condition, *pos)
*pos += replaced
*args = append(*args, f.Values...)
} else {
buf.WriteString(f.Condition)
}
}
func writeWhereCondition(buf common.BufferWriter, k string, pred string, anyConditions bool) bool {
if anyConditions {
buf.WriteString(" AND (")
} else {
buf.WriteRune('(')
anyConditions = true
}
Dialect.WriteIdentifier(buf, k)
buf.WriteString(pred)
buf.WriteRune(')')
return anyConditions
}
// WriteIdentifier writes escaped identifier.
func (pd *Postgres) WriteIdentifier(buf common.BufferWriter, ident string) {
if ident == "" {
panic("Identifier is empty string")
}
buf.WriteRune('"')
if strings.Contains(ident, ".") {
for _, char := range ident {
if char == '.' {
buf.WriteString("\".\"")
} else {
buf.WriteRune(char)
}
}
} else {
buf.WriteString(ident)
}
buf.WriteRune('"')
}
func remapPlaceholders(buf common.BufferWriter, statement string, start int64) int64 {
if !strings.Contains(statement, "$") {
buf.WriteString(statement)
return 0
}
highest := 0
pos := int(start) - 1 // 0-based
statement = rePlaceholder.ReplaceAllStringFunc(statement, func(s string) string {
i, _ := strconv.Atoi(s[1:])
if i > highest {
highest = i
}
sum := strconv.Itoa(pos + i)
return "$" + sum
})
buf.WriteString(statement)
return int64(highest)
}
func writeEqualityMapToSql(buf common.BufferWriter, eq map[string]interface{}, args *[]interface{}, anyConditions bool, pos *int64) bool {
for k, v := range eq {
if v == nil {
anyConditions = writeWhereCondition(buf, k, " IS NULL", anyConditions)
} else {
vVal := reflect.ValueOf(v)
if vVal.Kind() == reflect.Array || vVal.Kind() == reflect.Slice {
vValLen := vVal.Len()
if vValLen == 0 {
if vVal.IsNil() {
anyConditions = writeWhereCondition(buf, k, " IS NULL", anyConditions)
} else {
if anyConditions {
buf.WriteString(" AND (1=0)")
} else {
buf.WriteString("(1=0)")
}
}
} else if vValLen == 1 {
anyConditions = writeWhereCondition(buf, k, equalsPlaceholderTab[*pos], anyConditions)
*args = append(*args, vVal.Index(0).Interface())
*pos++
} else {
// " IN $n"
anyConditions = writeWhereCondition(buf, k, inPlaceholderTab[*pos], anyConditions)
*args = append(*args, v)
*pos++
}
} else {
anyConditions = writeWhereCondition(buf, k, equalsPlaceholderTab[*pos], anyConditions)
*args = append(*args, v)
*pos++
}
}
}
return anyConditions
}
// writeKVWhere writes "col1" = $1 AND "col2" = $2, ... "coln" = $n
func writeKVWhere(buf common.BufferWriter, columns []string, values []interface{}, args *[]interface{}, anyConditions bool, pos *int64) bool {
if len(columns) != len(values) {
panic("Mismatch of column and values")
}
for i, k := range columns {
v := values[i]
if v == nil {
anyConditions = writeWhereCondition(buf, k, " IS NULL", anyConditions)
} else if e, ok := v.(*Expression); ok {
start := pos
buf.WriteString(" = ")
// map relative $1, $2 placeholders to absolute
remapPlaceholders(buf, e.Sql, *start)
*args = append(*args, e.Args...)
*pos += int64(len(e.Args))
} else {
vVal := reflect.ValueOf(v)
if vVal.Kind() == reflect.Array || vVal.Kind() == reflect.Slice {
vValLen := vVal.Len()
if vValLen == 0 {
if vVal.IsNil() {
anyConditions = writeWhereCondition(buf, k, " IS NULL", anyConditions)
} else {
if anyConditions {
buf.WriteString(" AND (1=0)")
} else {
buf.WriteString("(1=0)")
}
}
} else if vValLen == 1 {
anyConditions = writeWhereCondition(buf, k, equalsPlaceholderTab[*pos], anyConditions)
*args = append(*args, vVal.Index(0).Interface())
*pos++
} else {
// " IN $n"
anyConditions = writeWhereCondition(buf, k, inPlaceholderTab[*pos], anyConditions)
*args = append(*args, v)
*pos++
}
} else {
anyConditions = writeWhereCondition(buf, k, equalsPlaceholderTab[*pos], anyConditions)
*args = append(*args, v)
*pos++
}
}
}
return anyConditions
}
// WriteStringLiteral writes an escaped string. No escape characters
// are allowed.
//
// Postgres 9.1+ does not allow any escape
// sequences by default. See http://www.postgresql.org/docs/9.3/interactive/sql-syntax-lexical.html#SQL-SYNTAX-STRINGS-ESCAPE
// In short, all backslashes are treated literally not as escape sequences.
func (pd *Postgres) WriteStringLiteral(buf common.BufferWriter, val string) {
if val == "" {
buf.WriteString("''")
return
}
hasTag := true
// don't use double dollar quote strings unless the string is long enough
if len(val) > 64 {
// if pgDollarTag unique tag is in string, try to create a new one (only once though)
hasTag = strings.Contains(val, pgDollarTag)
if hasTag {
randomizePgDollarTag()
hasTag = strings.Contains(val, pgDollarTag)
}
}
if hasTag {
buf.WriteRune('\'')
if strings.Contains(val, "'") {
for _, char := range val {
// apos
if char == '\'' {
buf.WriteString(`''`)
} else if char == 0 {
panic("postgres doesn't support NULL char in text, see http://stackoverflow.com/questions/1347646/postgres-error-on-insert-error-invalid-byte-sequence-for-encoding-utf8-0x0")
} else {
buf.WriteRune(char)
}
}
} else {
buf.WriteString(val)
}
buf.WriteRune('\'')
} else {
buf.WriteString(pgDollarTag)
buf.WriteString(val)
buf.WriteString(pgDollarTag)
}
}