检查Laravel迁移文件中是否存在列
问题描述：
Already I have a table name table_one. Now I want to add two more columns to it. Everything works fine so far. But in my method, I want to check a column exists or not in my table like dropIfExists('table').
/**
* Run the migrations.
*
* @return void
*/
public function up()
{
Schema::table('table_one', function (Blueprint $table) {
$table->string('column_one')->nullable();
$table->string('column_two')->nullable();
});
}
/**
* Reverse the migrations.
*
* @return void
*/
public function down()
{
Schema::table('table_one', function (Blueprint $table) {
// in here i want to check column_one and column_two exists or not
$table->dropColumn('column_one');
$table->dropColumn('column_two');
});
}
答
You need something just like this
public function down()
{
if (Schema::hasColumn('users', 'phone'))
{
Schema::table('users', function (Blueprint $table)
{
$table->dropColumn('phone');
});
}
}
答
Just break the schema up into two calls
public function up()
{
Schema::table('table_one', function (Blueprint $table) {
$table->dropColumn(['column_one', 'column_two']);
});
Schema::table('table_one', function (Blueprint $table) {
$table->string('column_one')->nullable();
$table->string('column_two')->nullable();
});
}