Safe Haskell | Safe-Inferred |
---|---|
Language | GHC2021 |
Database.Persist.Sql.Lifted.Expression.String
Synopsis
- lower_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- upper_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- trim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- ltrim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- rtrim_ :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s)
- length_ :: (SqlString s, Num a) => SqlExpr (Value s) -> SqlExpr (Value a)
- left_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s)
- right_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s)
- like :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool)
- ilike :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool)
- (%) :: SqlString s => SqlExpr (Value s)
- concat_ :: SqlString s => [SqlExpr (Value s)] -> SqlExpr (Value s)
- (++.) :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value s)
- castString :: (SqlString s, SqlString r) => SqlExpr (Value s) -> SqlExpr (Value r)
Documentation
length_ :: (SqlString s, Num a) => SqlExpr (Value s) -> SqlExpr (Value a) #
LENGTH
function.
@since 3.3.0
left_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s) #
LEFT
function.
@since 3.3.0
right_ :: (SqlString s, Num a) => (SqlExpr (Value s), SqlExpr (Value a)) -> SqlExpr (Value s) #
RIGHT
function.
@since 3.3.0
like :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool) infixr 2 #
LIKE
operator.
ilike :: SqlString s => SqlExpr (Value s) -> SqlExpr (Value s) -> SqlExpr (Value Bool) infixr 2 #
ILIKE
operator (case-insensitive LIKE
).
Supported by PostgreSQL only.
Since: esqueleto-2.2.3
concat_ :: SqlString s => [SqlExpr (Value s)] -> SqlExpr (Value s) #
The CONCAT
function with a variable number of
parameters. Supported by MySQL and PostgreSQL.
castString :: (SqlString s, SqlString r) => SqlExpr (Value s) -> SqlExpr (Value r) #
Cast a string type into Text
. This function
is very useful if you want to use newtype
s, or if you want
to apply functions such as like
to strings of different
types.
Safety: This is a slightly unsafe function, especially if
you have defined your own instances of SqlString
. Also,
since Maybe
is an instance of SqlString
, it's possible
to turn a nullable value into a non-nullable one. Avoid
using this function if possible.