diff --git a/app/src/main/java/org/jyutping/jyutping/extensions/CharCode.kt b/app/src/main/java/org/jyutping/jyutping/extensions/CharCode.kt
new file mode 100644
index 0000000..6e3c772
--- /dev/null
+++ b/app/src/main/java/org/jyutping/jyutping/extensions/CharCode.kt
@@ -0,0 +1,52 @@
+package org.jyutping.jyutping.extensions
+
+fun String.charcode(): Int? {
+        if (this.length >= 10) return null
+        val codes = this.mapNotNull { it.intercode() }
+        if (codes.size != this.length) return null
+        return codes.combined()
+}
+fun String.shortcutCharcode(): Int? {
+        if (this.length >= 10) return null
+        val codes = this.mapNotNull { it.intercode() }
+        if (codes.size != this.length) return null
+        val code = codes
+                .map { if (it == 44) 29 else it } // Replace 'y' with 'j'
+                .combined()
+        return code
+}
+
+fun Iterable<Int>.combined(): Int {
+        if (this.count() >= 10) return 0
+        return this.fold(0) { acc, i -> acc * 100 + i }
+}
+
+fun Char.intercode(): Int? = when (this) {
+        'a' -> 20
+        'b' -> 21
+        'c' -> 22
+        'd' -> 23
+        'e' -> 24
+        'f' -> 25
+        'g' -> 26
+        'h' -> 27
+        'i' -> 28
+        'j' -> 29
+        'k' -> 30
+        'l' -> 31
+        'm' -> 32
+        'n' -> 33
+        'o' -> 34
+        'p' -> 35
+        'q' -> 36
+        'r' -> 37
+        's' -> 38
+        't' -> 39
+        'u' -> 40
+        'v' -> 41
+        'w' -> 42
+        'x' -> 43
+        'y' -> 44
+        'z' -> 45
+        else -> null
+}
diff --git a/app/src/main/java/org/jyutping/jyutping/extensions/StringExtensions.kt b/app/src/main/java/org/jyutping/jyutping/extensions/StringExtensions.kt
index b1c5c0e..23fe494 100644
--- a/app/src/main/java/org/jyutping/jyutping/extensions/StringExtensions.kt
+++ b/app/src/main/java/org/jyutping/jyutping/extensions/StringExtensions.kt
@@ -13,45 +13,3 @@ val String.Companion.space: String
 
 val String.Companion.separator: String
         get() = "'"
-
-fun String.charcode(): Int? {
-        if (this.length >= 10) return null
-        val codes = this.mapNotNull { it.intercode() }
-        if (codes.size != this.length) return null
-        return codes.combined()
-}
-
-private fun Iterable<Int>.combined(): Int {
-        if (this.count() >= 10) return 0
-        return this.fold(0) { acc, i -> acc * 100 + i }
-}
-
-private fun Char.intercode(): Int? = when (this) {
-        'a' -> 20
-        'b' -> 21
-        'c' -> 22
-        'd' -> 23
-        'e' -> 24
-        'f' -> 25
-        'g' -> 26
-        'h' -> 27
-        'i' -> 28
-        'j' -> 29
-        'k' -> 30
-        'l' -> 31
-        'm' -> 32
-        'n' -> 33
-        'o' -> 34
-        'p' -> 35
-        'q' -> 36
-        'r' -> 37
-        's' -> 38
-        't' -> 39
-        'u' -> 40
-        'v' -> 41
-        'w' -> 42
-        'x' -> 43
-        'y' -> 44
-        'z' -> 45
-        else -> null
-}
diff --git a/app/src/main/java/org/jyutping/jyutping/keyboard/Engine.kt b/app/src/main/java/org/jyutping/jyutping/keyboard/Engine.kt
index ca2a7c4..fd79255 100644
--- a/app/src/main/java/org/jyutping/jyutping/keyboard/Engine.kt
+++ b/app/src/main/java/org/jyutping/jyutping/keyboard/Engine.kt
@@ -6,14 +6,18 @@ import org.jyutping.jyutping.utilities.DatabaseHelper
 
 object Engine {
         fun suggest(text: String, segmentation: Segmentation, db: DatabaseHelper): List<Candidate> {
+                if (db.canProcess(text).not()) return emptyList()
+                if (segmentation.maxLength() < 1) return processVerbatim(text, db)
                 return process(text, segmentation, db)
         }
         private fun processVerbatim(text: String, db: DatabaseHelper): List<Candidate> {
-                val rounds = text.indices.map { number ->
+                val rounds: MutableList<List<Candidate>> = mutableListOf()
+                for (number in text.indices) {
                         val leading = text.dropLast(number)
-                        return db.match(text = leading, input = leading) + db.shortcut(text = leading)
+                        val round = db.match(text = leading, input = leading) + db.shortcut(text = leading)
+                        rounds.add(round)
                 }
-                return rounds.flatten<Candidate>().distinct()
+                return rounds.flatten().distinct()
         }
         private fun process(text: String, segmentation: Segmentation, db: DatabaseHelper): List<Candidate> {
                 val primary = query(text, segmentation, db)
diff --git a/app/src/main/java/org/jyutping/jyutping/utilities/DatabaseHelper.kt b/app/src/main/java/org/jyutping/jyutping/utilities/DatabaseHelper.kt
index 3a9c669..ca1ac55 100644
--- a/app/src/main/java/org/jyutping/jyutping/utilities/DatabaseHelper.kt
+++ b/app/src/main/java/org/jyutping/jyutping/utilities/DatabaseHelper.kt
@@ -5,7 +5,9 @@ import android.database.sqlite.SQLiteDatabase
 import android.database.sqlite.SQLiteOpenHelper
 import org.jyutping.jyutping.extensions.charcode
 import org.jyutping.jyutping.extensions.convertedS2T
+import org.jyutping.jyutping.extensions.intercode
 import org.jyutping.jyutping.extensions.isIdeographic
+import org.jyutping.jyutping.extensions.shortcutCharcode
 import org.jyutping.jyutping.keyboard.Candidate
 import org.jyutping.jyutping.keyboard.SegmentToken
 import org.jyutping.jyutping.search.CantoneseLexicon
@@ -334,10 +336,23 @@ class DatabaseHelper(context: Context, databaseName: String) : SQLiteOpenHelper(
                 return null
         }
 
+        fun canProcess(text: String): Boolean {
+                val value = text.firstOrNull()?.intercode() ?: 0
+                if (value == 0) return false
+                val code = if (value == 44) 29 else value // Replace 'y' with 'j'
+                val command = "SELECT rowid FROM lexicontable WHERE shortcut = $code LIMIT 1;"
+                val cursor = this.readableDatabase.rawQuery(command, null)
+                if (cursor.moveToFirst()) {
+                        cursor.close()
+                        return true
+                } else {
+                        return false
+                }
+        }
         fun shortcut(text: String): List<Candidate> {
+                val code: Int = text.shortcutCharcode() ?: 0
+                if (code == 0) return emptyList()
                 val candidates: MutableList<Candidate> = mutableListOf()
-                if (text.isBlank()) return candidates
-                val code: Int = text.charcode() ?: 0
                 val command = "SELECT rowid, word, romanization FROM lexicontable WHERE shortcut = $code LIMIT 50;"
                 val cursor = this.readableDatabase.rawQuery(command, null)
                 while (cursor.moveToNext()) {
@@ -350,10 +365,10 @@ class DatabaseHelper(context: Context, databaseName: String) : SQLiteOpenHelper(
                 cursor.close()
                 return candidates
         }
-        fun match(text: String, input: String, mark: String? = null, limit: Int? = null): List<Candidate> {
-                val candidates: MutableList<Candidate> = mutableListOf()
-                if (text.isBlank()) return candidates
+        fun match(text: String, input: String, mark: String? = null): List<Candidate> {
+                if (text.isBlank()) return emptyList()
                 val code: Int = text.hashCode()
+                val candidates: MutableList<Candidate> = mutableListOf()
                 val command = "SELECT rowid, word, romanization FROM lexicontable WHERE ping = ${code};"
                 val cursor = this.readableDatabase.rawQuery(command, null)
                 while (cursor.moveToNext()) {