// regexp expression expects the target expression and pattern to be a string, if it's not, we add a cast function.
func (v *typeInferrer) handleRegexpExpr(x *ast.PatternRegexpExpr) {
x.SetType(types.NewFieldType(mysql.TypeLonglong))
x.Type.Charset = charset.CharsetBin
x.Type.Collate = charset.CollationBin
x.Expr = v.addCastToString(x.Expr)
x.Pattern = v.addCastToString(x.Pattern)
}
func (e *Evaluator) patternRegexp(p *ast.PatternRegexpExpr) bool {
var sexpr string
if p.Sexpr != nil {
sexpr = *p.Sexpr
} else {
expr := p.Expr.GetDatum()
if expr.IsNull() {
p.SetNull()
return true
}
var err error
sexpr, err = expr.ToString()
if err != nil {
e.err = errors.Errorf("non-string Expression in LIKE: %v (Value of type %T)", expr, expr)
return false
}
if ast.IsConstant(p.Expr) {
p.Sexpr = new(string)
*p.Sexpr = sexpr
}
}
re := p.Re
if re == nil {
pattern := p.Pattern.GetDatum()
if pattern.IsNull() {
p.SetNull()
return true
}
spattern, err := pattern.ToString()
if err != nil {
e.err = errors.Errorf("non-string pattern in LIKE: %v (Value of type %T)", pattern, pattern)
return false
}
if re, err = regexp.Compile(spattern); err != nil {
e.err = errors.Trace(err)
return false
}
if ast.IsConstant(p.Pattern) {
p.Re = re
}
}
match := re.MatchString(sexpr)
if p.Not {
match = !match
}
p.SetInt64(boolToInt64(match))
return true
}