calasql-query_3.0.1.5.source-code.From.scala Maven / Gradle / Ivy
package scalasql.query
import scalasql.core.{Context, Expr, ExprsToSql, LiveExprs, Queryable, SqlStr}
import scalasql.core.Context.From
import scalasql.core.SqlStr.SqlStringSyntax
/**
* Models a SQL `FROM` clause
*/
class TableRef(val value: Table.Base) extends From {
override def toString = s"TableRef(${Table.name(value)})"
def fromRefPrefix(prevContext: Context) = prevContext.config.tableNameMapper(Table.name(value))
def fromExprAliases(prevContext: Context): Seq[(Expr.Identity, SqlStr)] = Nil
def renderSql(name: SqlStr, prevContext: Context, liveExprs: LiveExprs) = {
SqlStr.raw(prevContext.config.tableNameMapper(Table.name(value))) + sql" " + name
}
}
/**
* Models a subquery: a `SELECT`, `VALUES`, nested `WITH`, etc.
*/
class SubqueryRef(val value: SubqueryRef.Wrapped) extends From {
def fromRefPrefix(prevContext: Context): String = "subquery"
def fromExprAliases(prevContext: Context) = SubqueryRef.Wrapped.exprAliases(value, prevContext)
def renderSql(name: SqlStr, prevContext: Context, liveExprs: LiveExprs) = {
val renderSql = SubqueryRef.Wrapped.renderer(value, prevContext)
sql"(${renderSql.render(liveExprs)}) $name"
}
}
object SubqueryRef {
trait Wrapped {
protected def selectExprAliases(prevContext: Context): Seq[(Expr.Identity, SqlStr)]
protected def selectRenderer(prevContext: Context): Wrapped.Renderer
}
object Wrapped {
def exprAliases(s: Wrapped, prevContext: Context) = s.selectExprAliases(prevContext)
def renderer(s: Wrapped, prevContext: Context) = s.selectRenderer(prevContext)
trait Renderer {
def render(liveExprs: LiveExprs): SqlStr
}
}
}
class WithCteRef(walked: Queryable.Walked) extends From {
def fromRefPrefix(prevContext: Context) = "cte"
def fromExprAliases(prevContext: Context) = {
ExprsToSql.selectColumnReferences(walked, prevContext)
}
def renderSql(name: SqlStr, prevContext: Context, liveExprs: LiveExprs) = {
name
}
}