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  • Data truncation when retrieving data from MySQL database with prepared statements

    - by KSiimson
    I have a script that retrieves multiple products using prepared statements. Like putting loops into loops, I have prepared statements in prepared statements - so there is a prepared statement for retrieving all products, a prepared statement to retrieve all images for that product, a prepared statement to get all attributes for that products, and so on. This does not work with one MySQLi instance, so I use multiple MySQLi objects that are opened and closed when needed. It usually works fine, but sometimes, especially when displaying multiple products, some data is truncated. For example - MicoLoans becomes MicoLoa. There was an actual spelling mistake here - now when I changed MicoLoans to MicroLoans, the same page displayed MicroLoa... So the same number of characters was truncated from the end. It is sort of consistent where it appears - for example there can be descriptions for 8 products, and description of 1 product is heavily truncated. When I add 9th product, the short description is still truncated for that same product as before. Any ideas?

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  • PHP, MySQL, jQuery, AJAX: json data returns correct response but frontend returns error

    - by Devner
    Hi all, I have a user registration form. I am doing server side validation on the fly via AJAX. The quick summary of my problem is that upon validating 2 fields, I get error for the second field validation. If I comment first field, then the 2nd field does not show any error. It has this weird behavior. More details below: The HTML, JS and Php code are below: HTML FORM: <form id="SignupForm" action=""> <fieldset> <legend>Free Signup</legend> <label for="username">Username</label> <input name="username" type="text" id="username" /><span id="status_username"></span><br /> <label for="email">Email</label> <input name="email" type="text" id="email" /><span id="status_email"></span><br /> <label for="confirm_email">Confirm Email</label> <input name="confirm_email" type="text" id="confirm_email" /><span id="status_confirm_email"></span><br /> </fieldset> <p> <input id="sbt" type="button" value="Submit form" /> </p> </form> JS: <script type="text/javascript"> $(document).ready(function() { $("#email").blur(function() { var email = $("#email").val(); var msgbox2 = $("#status_email"); if(email.length > 3) { $.ajax({ type: 'POST', url: 'check_ajax2.php', data: "email="+ email, dataType: 'json', cache: false, success: function(data) { if(data.success == 'y') { alert('Available'); } else { alert('Not Available'); } } }); } return false; }); $("#confirm_email").blur(function() { var confirm_email = $("#confirm_email").val(); var email = $("#email").val(); var msgbox3 = $("#status_confirm_email"); if(confirm_email.length > 3) { $.ajax({ type: 'POST', url: 'check_ajax2.php', data: 'confirm_email='+ confirm_email + '&email=' + email, dataType: 'json', cache: false, success: function(data) { if(data.success == 'y') { alert('Available'); } else { alert('Not Available'); } } , error: function (data) { alert('Some error'); } }); } return false; }); }); </script> PHP code: <?php //check_ajax2.php if(isset($_POST['email'])) { $email = $_POST['email']; $res = mysql_query("SELECT uid FROM members WHERE email = '$email' "); $i_exists = mysql_num_rows($res); if( 0 == $i_exists ) { $success = 'y'; $msg_email = 'Email available'; } else { $success = 'n'; $msg_email = 'Email is already in use.</font>'; } print json_encode(array('success' => $success, 'msg_email' => $msg_email)); } if(isset($_POST['confirm_email'])) { $confirm_email = $_POST['confirm_email']; $email = ( isset($_POST['email']) && trim($_POST['email']) != '' ? $_POST['email'] : '' ); $res = mysql_query("SELECT uid FROM members WHERE email = '$confirm_email' "); $i_exists = mysql_num_rows($res); if( 0 == $i_exists ) { if( isset($email) && isset($confirm_email) && $email == $confirm_email ) { $success = 'y'; $msg_confirm_email = 'Email available and match'; } else { $success = 'n'; $msg_confirm_email = 'Email and Confirm Email do NOT match.'; } } else { $success = 'n'; $msg_confirm_email = 'Email already exists.'; } print json_encode(array('success' => $success, 'msg_confirm_email' => $msg_confirm_email)); } ?> THE PROBLEM: As long as I am validating the $_POST['email'] as well as $_POST['confirm_email'] in the check_ajax2.php file, the validation for confirm_email field always returns an error. With my limited knowledge of Firebug, however, I did find out that the following were the responses when I entered email and confirm_email in the fields: RESPONSE 1: {"success":"y","msg_email":"Email available"} RESPONSE 2: {"success":"y","msg_email":"Email available"}{"success":"n","msg_confirm_email":"Email and Confirm Email do NOT match."} Although the RESPONSE 2 shows that we are receiving the correct message via msg_confirm_email, in the front end, the alert 'Some error' is popping up (I have enabled the alert for debugging). I have spent 48 hours trying to change every part of the code wherever possible, but with only little success. What is weird about this is that if I comment the validation for $_POST['email'] field completely, then the validation for $_POST['confirm_email'] field is displaying correctly without any errors. If I enable it back, it is validating email field correctly, but when it reaches the point of validating confirm_email field, it is again showing me the error. I have also tried renaming success variable in check_ajax2.php page to other different names for both $_POST['email'] and $_POST['confirm_email'] but no success. I will be adding more fields in the form and validating within the check_ajax2.php page. So I am not planning on using different ajax pages for validating each of those fields (and I don't think it's smart to do it that way). I am not a jquery or AJAX guru, so all help in resolving this issue is highly appreciated. Thank you in advance.

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  • MySQL Dynamicly determine the tabel to use with inner join

    - by user366990
    He guys, I'm stuck with a problem and I hope someone can help me out. I have a date. For example 2009-10-1. This date is used to check in which season I am working. This could be summer or winter. If whe are in the summer the table to use for my inner join whould be 'summer09_rooms'. If winter 'winter09_rooms'. So I basicly whant to do a CASE WHEN in my INNER JOIN. How to accomplish this. The query would look like this: SELECT name, arrival_date, departure_date FROM holliday a INNER JOIN ( CASE when arrival_date BETWEEN 2009-10-1 AND 2009-4-1 THEN summer09_rooms b ELSE winter09_rooms b END ) ON a.dossier=b.dossier Of course this query isn't working but now I hope you'l see what I want to accomplish. Kind regards, Digital Human

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  • mysql GROUP_CONCAT

    - by user301766
    I want to list all users with their corropsonding user class. Here are simplified versions of my tables CREATE TABLE users ( user_id INT NOT NULL AUTO_INCREMENT, user_class VARCHAR(100), PRIMARY KEY (user_id) ); INSERT INTO users VALUES (1, '1'), (2, '2'), (3, '1,2'); CREATE TABLE classes ( class_id INT NOT NULL AUTO_INCREMENT, class_name VARCHAR(100), PRIMARY KEY (class_id) ); INSERT INTO classes VALUES (1, 'Class 1'), (2, 'Class 2'); And this is the query statement I am trying to use but is only returning the first matching user class and not a concatenated list as hoped. SELECT user_id, GROUP_CONCAT(DISTINCT class_name SEPARATOR ",") AS class_name FROM users, classes WHERE user_class IN (class_id) GROUP BY user_id; Actual Output +---------+------------+ | user_id | class_name | +---------+------------+ | 1 | Class 1 | | 2 | Class 2 | | 3 | Class 1 | +---------+------------+ Wanted Output +---------+---------------------+ | user_id | class_name | +---------+---------------------+ | 1 | Class 1 | | 2 | Class 2 | | 3 | Class 1, Class 2 | +---------+---------------------+ Thanks in advance

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  • Single Large v/s Multiple Small MySQL tables for storing Options

    - by Prasad
    Hi there, I'm aware of several question on this forum relating to this. But I'm not talking about splitting tables for the same entity (like user for example) Suppose I have a huge options table that stores list options like Gender, Marital Status, and many more domain specific groups with same structure. I plan to capture in a OPTIONS table. Another simple option is to have the field set as ENUM, but there are disadvantages of that as well. http://www.brandonsavage.net/why-you-should-replace-enum-with-something-else/ OPTIONS Table: option_id <will be referred instead of the name> name value group Query: select .. from options where group = '15' - Since this table is expected to be multi-tenant, the no of rows could grow drastically. - I believe splitting the tables instead of finding by the group would be easier to write & faster to execute. - or perhaps partitioning by the group or tenant? Pl suggest. Thanks

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  • MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'

    - by user198729
    SELECT u.id AS u__id, u.username AS u__username, p.id AS p__id, p.phonenumber AS p__phonenumber, p.user_id AS p__user_id FROM user u INNER JOIN phonenumber p ON u.id = p.user_id WHERE u.id IN (SELECT DISTINCT u2.id FROM user u2 INNER JOIN phonenumber p2 ON u2.id = p2.user_id LIMIT 20) This query is from here: http://www.doctrine-project.org/documentation/manual/1_2/en/dql-doctrine-query-language It's supposed to work on all DBMS ,but not in fact

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  • MYSQL Inner Join two table over two keys

    - by bertsisterwanda
    I am doing a query to return all users shopping carts, stored in the sb_carts table. The product information stored in sb_carts is referenced over two keys product_sku and school_id. It needs to reference both to return a unique product with unique stock levels etc. When I execute the following query it returns one row, I am expecting 3 rows. I have tried breaking the inner join into two separate joins but this still returns only 1 result. joining only on one key has the desired result, but may be retuning the wrong product. A left join returns 3 rows but some data is missing product specific Here is a simplified example of what I am doing SELECT sb_carts.product_sku FROM sb_carts INNER JOIN sb_products ON sb_products.sku = sb_carts.product_sku AND sb_products.school_id = sb_carts.school_id WHERE sb_carts.order_id = 0 AND sb_carts.user_id = 2 GROUP BY sb_carts.cart_id

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  • Php, mysql selection

    - by cosy
    I have this table ATTRIBUTE id name um 12 capacity MB;GB;TB And this table2 : id id_attribute id_product name value um 1 12 40 hdd maxtor 30 GB 2 12 41 hdd maxtor 40 GB 3 12 42 hdd y 1 TB How can i select from table2 in this order : 30GB 40GB 1TB? Thanks a lot!

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  • Optimize MySQL query (ngrams, COUNT(), GROUP BY, ORDER BY)

    - by Gerardo
    I have a database with thousands of companies and their locations. I have implemented n-grams to optimize search. I am making one query to retrieve all the companies that match with the search query and another one to get a list with their locations and the number of companies in each location. The query I am trying to optimize is the latter. Maybe the problem is this: Every company ('anunciante') has a field ('estado') to make logical deletes. So, if 'estado' equals 1, the company should be retrieved. When I run the EXPLAIN command, it shows that it goes through almost 40k rows, when the actual result (the reality matching companies) are 80. How can I optimize this? This is my query (XXX represent the n-grams for the search query): SELECT provincias.provincia AS provincia, provincias.id, COUNT(*) AS cantidad FROM anunciantes JOIN anunciante_invertido AS a_i0 ON anunciantes.id = a_i0.id_anunciante JOIN indice_invertido AS indice0 ON a_i0.id_invertido = indice0.id LEFT OUTER JOIN domicilios ON anunciantes.id = domicilios.id_anunciante LEFT OUTER JOIN localidades ON domicilios.id_localidad = localidades.id LEFT OUTER JOIN provincias ON provincias.id = localidades.id_provincia WHERE anunciantes.estado = 1 AND indice0.id IN (SELECT invertido_ngrama.id_palabra FROM invertido_ngrama JOIN ngrama ON ngrama.id = invertido_ngrama.id_ngrama WHERE ngrama.ngrama = 'XXX') AND indice0.id IN (SELECT invertido_ngrama.id_palabra FROM invertido_ngrama JOIN ngrama ON ngrama.id = invertido_ngrama.id_ngrama WHERE ngrama.ngrama = 'XXX') AND indice0.id IN (SELECT invertido_ngrama.id_palabra FROM invertido_ngrama JOIN ngrama ON ngrama.id = invertido_ngrama.id_ngrama WHERE ngrama.ngrama = 'XXX') AND indice0.id IN (SELECT invertido_ngrama.id_palabra FROM invertido_ngrama JOIN ngrama ON ngrama.id = invertido_ngrama.id_ngrama WHERE ngrama.ngrama = 'XXX') AND indice0.id IN (SELECT invertido_ngrama.id_palabra FROM invertido_ngrama JOIN ngrama ON ngrama.id = invertido_ngrama.id_ngrama WHERE ngrama.ngrama = 'XXX') GROUP BY provincias.id ORDER BY cantidad DESC And this is the query explained (hope it can be read in this format): id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY anunciantes ref PRIMARY,estado estado 1 const 36669 Using index; Using temporary; Using filesort 1 PRIMARY domicilios ref id_anunciante id_anunciante 4 db84771_viaempresas.anunciantes.id 1 1 PRIMARY localidades eq_ref PRIMARY PRIMARY 4 db84771_viaempresas.domicilios.id_localidad 1 1 PRIMARY provincias eq_ref PRIMARY PRIMARY 4 db84771_viaempresas.localidades.id_provincia 1 1 PRIMARY a_i0 ref PRIMARY,id_anunciante,id_invertido PRIMARY 4 db84771_viaempresas.anunciantes.id 1 Using where; Using index 1 PRIMARY indice0 eq_ref PRIMARY PRIMARY 4 db84771_viaempresas.a_i0.id_invertido 1 Using index 6 DEPENDENT SUBQUERY ngrama const PRIMARY,ngrama ngrama 5 const 1 Using index 6 DEPENDENT SUBQUERY invertido_ngrama eq_ref PRIMARY,id_palabra,id_ngrama PRIMARY 8 func,const 1 Using index 5 DEPENDENT SUBQUERY ngrama const PRIMARY,ngrama ngrama 5 const 1 Using index 5 DEPENDENT SUBQUERY invertido_ngrama eq_ref PRIMARY,id_palabra,id_ngrama PRIMARY 8 func,const 1 Using index 4 DEPENDENT SUBQUERY ngrama const PRIMARY,ngrama ngrama 5 const 1 Using index 4 DEPENDENT SUBQUERY invertido_ngrama eq_ref PRIMARY,id_palabra,id_ngrama PRIMARY 8 func,const 1 Using index 3 DEPENDENT SUBQUERY ngrama const PRIMARY,ngrama ngrama 5 const 1 Using index 3 DEPENDENT SUBQUERY invertido_ngrama eq_ref PRIMARY,id_palabra,id_ngrama PRIMARY 8 func,const 1 Using index 2 DEPENDENT SUBQUERY ngrama const PRIMARY,ngrama ngrama 5 const 1 Using index 2 DEPENDENT SUBQUERY invertido_ngrama eq_ref PRIMARY,id_palabra,id_ngrama PRIMARY 8 func,const 1 Using index

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  • MYSQL get the name from another table that is associated with the first table

    - by Juan Gonzales
    I can't figure out why this statement is not working SELECT myChurches.id AS id, myChurches.church_name AS church_name FROM myChurches INNER JOIN church_staff ON church_staff.church_id=myChurches.id WHERE church_staff.mem_id='$logOptions_id' ORDER BY myChurches.church_name ASC Basically I need to find the person's that are staff members of a church from one table and want to get the 'name' of that church FROM the 'myChurches' table. Hopefully that makes sense. Thanks in advance

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  • Improve speed of a JOIN in MySQL

    - by ran2
    Dear all, I know there a similar threads around, but this is really the first time I realize that query speed might affect me - so it´s not that easy for me to really make the transfer from other folks problems. That being said I have using the following query successfully with smaller data, but if I use it on what are mildly large tables (about 120,000 records). I am waiting for hours. INSERT INTO anothertable (id,someint1,someint1,somevarchar1,somevarchar1) SELECT DISTINCT md.id,md.someint1,md.someint1,md.somevarchar1,pd.somevarchar1 from table1 AS md JOIN table2 AS pd ON (md.id = pd.id); Tables 1 and 2 contain about 120,000 records. The query has been running for almost 2 hours right now. Is this normal? Do I just have to wait. I really have no idea, but I am pretty sure that one could do it better since it´s my very first try. I read about indexing, but dont know yet what to index in my case? Thanks for any suggestions - feel free to point my to the very beginners guides ! best matt

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  • MYSQL and the LIMIT clause

    - by Lizard
    I was wondering if adding a LIMIT 1 to a query would speed up the processing? For example... I have a query that will most of the time return 1 result, but will occasionaly return 10's, 100's or even 1000's of records. But I will only ever want the first record. Would the limit 1 speed things up or make no difference? I know I could use GROUP BY to return 1 result but that would just add more computation. Any thoughts gladly accepted! Thanks

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  • Retrieve part of a MySQL column with PHP

    - by Gerardo Marset
    For instance, if I have the following table: +----+---+----------+ | id | a | position | +----+---+----------+ | 0 | 0 | 0 | | 1 | 0 | 1 | | 2 | 1 | 4 | | 3 | 1 | 9 | | 4 | 1 | 6 | | 5 | 1 | 1 | +----+---+----------+ and I want to get an array that contains the first 100 values from position where a is 1 in ascending order, what would I do? Im guessing something like this: $col = mysql_fetch_array( mysql_query(' SELECT `position` FROM `table` WHERE `a`="1" ORDER BY `position` ASC LIMIT 100 ')); I'd expect to get the following array: +-------+-------+ | index | value | +-------+-------+ | 0 | 1 | | 1 | 4 | | 2 | 6 | | 3 | 9 | +-------+-------+ but it doesn't work. ¿What should I do to make it work? Thanks

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  • PHP MySQL INSERT fails due to unique constraint

    - by sjw
    On insert I am catching the unique constraint mysql_errno() 1062. This works fine but I want to find the existing row to re-instate or modify it. Is there are method to obtain the row id on insert fail? I tried mysql_insert_id() but realised that would only return the row I'm inserting (or failed to insert) therefore, I get 0. Is there no option but to issue another mysql_query and simply perform a select on the duplicate value? I just want to make sure there is no better, quicker, more economical way to do this.

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  • MySql Query lag time?

    - by Click Upvote
    When there are multiple PHP scripts running in parallel, each making an UPDATE query to the same record in the same table repeatedly, is it possible for there to be a 'lag time' before the table is updated with each query? I have basically 5-6 instances of a PHP script running in parallel, having been launched via cron. Each script gets all the records in the items table, and then loops through them and processes them. However, to avoid processing the same item more than once, I store the id of the last item being processed in a seperate table. So this is how my code works: function getCurrentItem() { $sql = "SELECT currentItemId from settings"; $result = $this->db->query($sql); return $result->get('currentItemId'); } function setCurrentItem($id) { $sql = "UPDATE settings SET currentItemId='$id'"; $this->db->query($sql); } $currentItem = $this->getCurrentItem(); $sql = "SELECT * FROM items WHERE status='pending' AND id > $currentItem'"; $result = $this->db->query($sql); $items = $result->getAll(); foreach ($items as $i) { //Check if $i has been processed by a different instance of the script, and if so, //leave it untouched. if ($this->getCurrentItem() > $i->id) continue; $this->setCurrentItem($i->id); // Process the item here } But despite of all the precautions, most items are being processed more than once. Which makes me think that there is some lag time between the update queries being run by the PHP script, and when the database actually updates the record. Is it true? And if so, what other mechanism should I use to ensure that the PHP scripts always get only the latest currentItemId even when there are multiple scripts running in parrallel? Would using a text file instead of the db help?

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  • MySQL SELECT Statment issue

    - by mouthpiec
    Hi, I have the following query which returns 2 tuples SELECT bar_id, bar_name, town_name, bar_telephone, subscription_type_id, type FROM towns, subscriptiontype, regions, bar LEFT JOIN barpictures bp ON bar.bar_id = bp.bar_id_fk WHERE town_id = town_id_fk AND bar.test_field = 0 AND subscription_type_id = subscription_type_id_fk AND region_id = region_id_fk AND (type like 'logo%' OR type IS NULL) The main difference between the tuples is that one has 'type' = logo and the other tuple has 'type' = logo_large. I need that instead of having two tuples, I need that I have 2 type attributes, one holding the "logo" and the other the "logo_large" eg bar_id, bar_name, town_name, bar_telephone, subscription_type_id, type1, type2 is this possible

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  • Creating a [materialised]view from generic data in Oracle/Mysql

    - by Andrew White
    I have a generic datamodel with 3 tables CREATE TABLE Properties ( propertyId int(11) NOT NULL AUTO_INCREMENT, name varchar(80) NOT NULL ) CREATE TABLE Customers ( customerId int(11) NOT NULL AUTO_INCREMENT, customerName varchar(80) NOT NULL ) CREATE TABLE PropertyValues ( propertyId int(11) NOT NULL, customerId int(11) NOT NULL, value varchar(80) NOT NULL ) INSERT INTO Properties VALUES (1, 'Age'); INSERT INTO Properties VALUES (2, 'Weight'); INSERT INTO Customers VALUES (1, 'Bob'); INSERT INTO Customers VALUES (2, 'Tom'); INSERT INTO PropertyValues VALUES (1, 1, '34'); INSERT INTO PropertyValues VALUES (2, 1, '80KG'); INSERT INTO PropertyValues VALUES (1, 2, '24'); INSERT INTO PropertyValues VALUES (2, 2, '53KG'); What I would like to do is create a view that has as columns all the ROWS in Properties and has as rows the entries in Customers. The column values are populated from PropertyValues. e.g. customerId Age Weight 1 34 80KG 2 24 53KG I'm thinking I need a stored procedure to do this and perhaps a materialised view (the entries in the table "Properties" change rarely). Any tips?

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  • Validating Login / Changing User settings / Php Mysql

    - by Marcelo
    Hi everyone, my questions are about login, and changing already saved data. (Q1) 'Till now I've only saved input in the tables of the database (registration steps), now I need to check if the input (login steps), are the same of my table in database, in fact I have 3 types of users, then I'll have to check 3 kind of tables. Then if the input data matches with one of those 3 tables I will redirect the user to his specific area. I'm thinking about saved the submitted data $login=$_REQUEST['login']; and $password=$_REQUEST['password']; and compare with the login column in the database. Then if the login matches, I'll compare the password submitted with the one in the row, not in the column. But I don't know how to do this search and comparison,neither what to use. Then if both matches I'll redirect the user. Else I'll send an login error message. (this I know how to do) (Q2) What if need to change an already saved user ? For example to change an email address. My changing user's data web page is exactly the same like the registration user web page. Can I load the already saved options and values of registration (table user for example). Then the user will change whatever he thinks it's necessary, and then when he submits the new information, they would not create a new row in my table, but just be overwritten the old information? How can I do this? Sorry for any mistake in English, and Thanks for the attention.

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  • mysql display each day in a month

    - by Jason
    during a month, display the infor each date, order by date, but this infor is empty in some day. how can i still display each day as a row? Product date ----------------- 20 2008-01-01 10 2008-01-02 20 2008-01-03 10 2008-01-05 09 2008-01-08 30 2008-01-09 result: Product date ----------------- 20 2008-01-01 10 2008-01-02 20 2008-01-03 0 2008-01-04 10 2008-01-05 0 2008-01-06 0 2008-01-07 09 2008-01-08 30 2008-01-09

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  • Mysql Select 1:n

    - by clinisbut
    Hello, I have two tables that relates 1:n content --------- - id - title - text content_meta ------------- - id - content_id - meta_key - meta_value A content can have multiple content_meta registers associated to it. Typically content_meta will contain the category, tags, descriptions and all that stuff, so I really don't know the number of registers a content will have. What I want to accomplish is to take the content register and also all the related registers in content_meta in a single query. I've tried the subselect approachment but seems that I can only get one register/column (¿?) SELECT content.*, ( SELECT * FROM content_meta WHERE content_id = content.id ) FROM content This query complains that "Operand should contain 1 column(s)", so changing the '*' by for example meta_key clears the error, but returns a NULL for this subselect... SELECT content.*, ( SELECT meta_key FROM content_meta WHERE content_id = content.id ) FROM content Can anybody show me where to go from here please?

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  • Deeply nested subqueries for traversing trees in MySQL

    - by nickf
    I have a table in my database where I store a tree structure using the hybrid Nested Set (MPTT) model (the one which has lft and rght values) and the Adjacency List model (storing parent_id on each node). my_table (id, parent_id, lft, rght, alias) This question doesn't relate to any of the MPTT aspects of the tree but I thought I'd leave it in in case anyone had a good idea about how to leverage that. I want to convert a path of aliases to a specific node. For example: "users.admins.nickf" would find the node with alias "nickf" which is a child of one with alias "admins" which is a child of "users" which is at the root. There is a unique index on (parent_id, alias). I started out by writing the function so it would split the path to its parts, then query the database one by one: SELECT `id` FROM `my_table` WHERE `parent_id` IS NULL AND `alias` = 'users';-- 1 SELECT `id` FROM `my_table` WHERE `parent_id` = 1 AND `alias` = 'admins'; -- 8 SELECT `id` FROM `my_table` WHERE `parent_id` = 8 AND `alias` = 'nickf'; -- 37 But then I realised I could do it with a single query, using a variable amount of nesting: SELECT `id` FROM `my_table` WHERE `parent_id` = ( SELECT `id` FROM `my_table` WHERE `parent_id` = ( SELECT `id` FROM `my_table` WHERE `parent_id` IS NULL AND `alias` = 'users' ) AND `alias` = 'admins' ) AND `alias` = 'nickf'; Since the number of sub-queries is dependent on the number of steps in the path, am I going to run into issues with having too many subqueries? (If there even is such a thing) Are there any better/smarter ways to perform this query?

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