qlite: add upsert support

1 files changed, 110 insertions, 0 deletions

diff --git a/qlite/src/upsert_builder.vala b/qlite/src/upsert_builder.vala
new file mode 100644
index 00000000..eb835027
--- /dev/null
+++ b/qlite/src/upsert_builder.vala
@@ -0,0 +1,110 @@
+using Sqlite;
+
+namespace Qlite {
+
+public class UpsertBuilder : StatementBuilder {
+    // INTO [...]
+    private Table table;
+    private string table_name;
+
+    // VALUES [...]
+    private StatementBuilder.AbstractField[] keys = {};
+    private StatementBuilder.AbstractField[] fields = {};
+
+    internal UpsertBuilder(Database db, Table table) {
+        base(db);
+        this.table = table;
+        this.table_name = table.name;
+    }
+
+    public UpsertBuilder value<T>(Column<T> column, T value, bool key = false) {
+        if (key) {
+            keys += new Field<T>(column, value);
+        } else {
+            fields += new Field<T>(column, value);
+        }
+        return this;
+    }
+
+    public UpsertBuilder value_null<T>(Column<T> column) throws DatabaseError {
+        if (column.not_null) throw new DatabaseError.ILLEGAL_QUERY(@"Can't set non-null column $(column.name) to null");
+        fields += new NullField<T>(column);
+        return this;
+    }
+
+    internal override Statement prepare() throws DatabaseError {
+        throw new DatabaseError.NOT_SUPPORTED("prepare() not available for upsert.");
+    }
+
+    internal Statement prepare_update() {
+        string update_set_list = "";
+        string update_where_list = "";
+        for (int i = 0; i < fields.length; i++) {
+            if (i != 0) {
+                update_set_list += ", ";
+            }
+            update_set_list += @"$(((!)fields[i].column).name) = ?";
+        }
+        for (int i = 0; i < keys.length; i++) {
+            if (i != 0) {
+                update_where_list += " AND ";
+            }
+            update_where_list += @"$(((!)keys[i].column).name) = ?";
+        }
+
+        string sql = @"UPDATE $table_name SET $update_set_list WHERE $update_where_list";
+
+        Statement stmt = db.prepare(sql);
+        for (int i = 0; i < fields.length; i++) {
+            fields[i].bind(stmt, i + 1);
+        }
+        for (int i = 0; i < keys.length; i++) {
+            keys[i].bind(stmt, i + fields.length + 1);
+        }
+
+        return stmt;
+    }
+
+    internal Statement prepare_insert() {
+        string insert_field_list = "";
+        string insert_value_qs = "";
+        for (int i = 0; i < fields.length; i++) {
+            if (i != 0) {
+                insert_value_qs += ", ";
+                insert_field_list += ", ";
+            }
+            insert_field_list += ((!)fields[i].column).name;
+            insert_value_qs += "?";
+        }
+        for (int i = 0; i < keys.length; i++) {
+            if (i != 0 || fields.length > 0) {
+                insert_value_qs += ", ";
+                insert_field_list += ", ";
+            }
+            insert_field_list += ((!)keys[i].column).name;
+            insert_value_qs += "?";
+        }
+
+        string sql = @"INSERT OR IGNORE INTO $table_name ($insert_field_list) VALUES ($insert_value_qs)";
+
+        Statement stmt = db.prepare(sql);
+        for (int i = 0; i < fields.length; i++) {
+            fields[i].bind(stmt, i + 1);
+        }
+        for (int i = 0; i < keys.length; i++) {
+            keys[i].bind(stmt, i + fields.length + 1);
+        }
+
+        return stmt;
+    }
+
+    public int64 perform() throws DatabaseError {
+        if (prepare_update().step() != DONE || prepare_insert().step() != DONE) {
+            throw new DatabaseError.EXEC_ERROR(@"SQLite error: $(db.errcode()) - $(db.errmsg())");
+        }
+        return db.last_insert_rowid();
+    }
+
+}
+
+}
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