fix: EXPOSED-580 MigrationsUtils.statementsRequiredForDatabaseMigration throws an error when a table is passed that does not already exist in the database (#2271)

The problem was in the `existingIndices` function. For some dialects, querying indices for a table that does not exist throws an error. This is fixed in the `statementsRequiredForDatabaseMigration` function by passing only tables that exist when invoking the `mappingConsistenceRequiredStatements` function.

Author: joc-a

exposed-migration/src/main/kotlin/MigrationUtils.kt

@@ -82,7 +82,7 @@ object MigrationUtils {
 
         val modifyTablesStatements = logTimeSpent("Checking mapping consistence", withLogs) {
             mappingConsistenceRequiredStatements(
-                tables = tables,
+                tables = tablesToAlter.toTypedArray(),
                 withLogs
             ).filter { it !in (createStatements + alterStatements) }
         }

exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/ddl/DatabaseMigrationTests.kt

@@ -133,6 +133,23 @@ class DatabaseMigrationTests : DatabaseTestsBase() {
         }
     }
 
+    @Test
+    fun testCreateStatementsGeneratedForTablesThatDoNotExist() {
+        val tester = object : Table("tester") {
+            val bar = char("bar")
+        }
+
+        withDb {
+            val statements = MigrationUtils.statementsRequiredForDatabaseMigration(tester, withLogs = false)
+            assertEquals(1, statements.size)
+            assertEquals(
+                "CREATE TABLE ${addIfNotExistsIfSupported()}${tester.nameInDatabaseCase()} " +
+                    "(${"bar".inProperCase()} CHAR NOT NULL)",
+                statements.first()
+            )
+        }
+    }
+
     @Test
     fun testDropUnmappedColumnsStatementsIdentical() {
         val t1 = object : Table("foo") {