SQL query from multiple columns with prepared statement - mysql

I want to be able to search and return results across the majority of columns in a mysql table. I considered using a myisam db and a full text search, but decided that because of the performance hit it would be better to stick with innodb. I also briefly considered using something like Solr, but a solution like that seems like overkill in my situation.
I am simply trying to add search functionality to a database of contact information. When the user enters say "Smith" I want the result to return and display all table rows where the first name, last name or even address contains the word Smith etc.
Tell me if this is the wrong approach, but I have settled on using a standard SQL string set up like this:
SELECT * FROM contacts WHERE firstName LIKE ? OR lastName LIKE ? OR email LIKE ?
Of course the actual query string will be considerably longer than this example because it will include most of the columns in the table.
1) I prefer to use prepared statements when querying the database for security, but when I set the sql string up how it is above, the code looks for a separate statement for each ?. How can I just repeat the same "LIKE ?" for each column? Or is there a way to set this up similar to:
SELECT * FROM contacts WHERE firstName, lastName, email LIKE ?
When I initially pass the string into the preparedstatement, I surround it with wildcards (%).
2) Will I be able to search both VARCHAR and INT columns?
EDIT: I ended up using a small portion of the Spring framework so I could be able to use named parameters. Unfortunately JDBC does not have this functionality. This meant including a small portion of the Spring framework in my build path so I could use the jdbc jar. Alternatively I could have passed in my one search string for each parameter in the query string, but this would result is ugly/hard to read code and I didn't want to hack around using the same string which is why I opted for using named parameters.


No you can't do that. You need to do it how you have it in the first query:
SELECT * FROM contacts WHERE firstName LIKE ? OR lastName LIKE ? OR email LIKE ?

Related

How to match a an exact piece of string with full stop in MySQL Full text search?

I have a table "employee" in Mysql, I decide to use FULL TEXT SEARCH INDEX for this.
employee table has a name column and values are like this
'ramakrishna',
'ramakrishna.hande',
'Ramakrishna.Hande',
'hande'
Now I want to write a query which fetches me 'ramakrishna.hande' and 'Ramakrishna.Hande'.
I wrote
SELECT * FROM employee WHERE MATCH(name) AGAINST("ramakrishna.hande");
But it fetches me everything from above list. I want to avoid this . I am using Scala as the programming language which I am using for executing MySQL query.
Is there a way to solve it ?

Searching table for fields using multiple possible combinations and wildcards

If in a simple customers table:
customers (first_name varchar(40), last_name varchar(40))
i would like to run a search by customer name, i can do:
[MYSQL...] WHERE (customers.first_name LIKE "%john%" OR customers.last_name LIKE "%john%")
However, if someone uses the search field in the front end to search for a full name, such as john arbuckle, i won't be getting any results.
What is the most effective and easiest way to run this query correctly in MySQL so that it can yield the desired results without losing the wildcard search capability?
The only thing i can think of is to split the string by whitespaces and run multiple logical comparison combinations for each string component. But is that really the way to go? Isn't there perhaps a way to combine fields when comparing their values?

Get the column name that match string comparison on multiple column-string comparison

Im building a simple search system, I have a simple form and I'm doing a query like this:
Select * from table where column_a like'%term%' or columnn_b like '%term%' or column_c like'%term%';
It is possible to determine which column was that the string %term% match (without using a bunch of if statements)?, actually I'm using CakePHP, but at this point I will not care if I need to build the query manually.

No, the identity of the matched column is lost in the evaluation of your or clauses. You'll need to do some post-processing (i.e., the "bunch of if statements" you were trying to avoid) to identify exactly which column in your result set matched.

is there a "best way" to short circuit a mysql query

I have a situation where I'm assembling a query based on user provided criteria and want to figure out what the most efficient way is to do this.
If I have a table that looks like this:
int id | varchar phone | varchar email | varchar RFID
and the user will pass in an array which defines the order (and items) with which they'd like to look up a user which *could look like this:
["id","email","phone"]
or it could look like this:
["email"]
or it could look like this:
["phone","rfid"]
or any other possible combination of those 4 fields.
Based on what I receive I need to look the user up in the order in which these fields arrived and if I find a match, I don't want to keep looking.
In other words if the input is
["email","rfid","phone"]
and I look into the db and find a user with the provided email, I don't want to keep looking to see if their rfid also matches, I just want to return said user.
However, if I don't find such an email, then I want to move on to the rfid.
So, in the various tests I've done (mostly playing with a case statement in the where clause) my results have been really terrible. Frequently taking almost a second to return a value, as opposed to taking <50ms when I simplify the where to search for the individual field.
I should note that all these fields are indexed.
So... my question is, should I just bite the bullet and make as many sql calls as there are items in the incoming array, or is there some really efficient way to structure a single query that will not bog down the system as my various attempts have.
I recognize that this may be too abstract a question, but am hoping that there's some mechanism for just such a use that I'm simply overlooking.

I don't think there's any good way to do a short-circuit in SQL. You can construct a WHERE clause that uses OR to combine the critiera, but doing this generally prevents it from using the indexes. You can use a UNION like this:
SELECT * FROM
(SELECT 1 precedence, table.*
FROM table
WHERE field1 = 'value'
UNION
SELECT 2 precedence, table.*
FROM table
WHERE field2 = 'value'
...
) x
ORDER BY precedence
LIMIT 1
where you replace field1, field2, etc. with the field names from the input array. This will produce the desired results in one query, but it will have to perform all the sub-queries, it won't short-circuit.
The best solution is probably to solve it in the application code. Loop through the fields in the input, and perform a query for just that field. When you get a result, break out of the loop and return it.

how to search several columns in a sql query using concat and UPPER

So I have a DB and a web page where I want to display the result of my db search
I have try a couple ways both work but they are incomplete for what I want to accomplish
I want to be able to search my table columns id,Id_Nombre,Pais,Estado,Ciudad,website all of them with a word or several words from my search text.
this code works but I have to type exactly the word it's case sensitive:
$query = "SELECT * FROM Medios_table WHERE concat(id,Id_Nombre,Pais,Estado,Ciudad,website) LIKE '%$Busqueda%'";
so as a result i I type a word like "People" in my search box and in my data base that word is type in any of those columns as "people" it wont find it.
second code I use works but only using one column
$query = "SELECT * FROM Medios_table WHERE UPPER(Id_Nombre) LIKE UPPER('%$Busqueda%')";
the result for this code is great since it will find it no matter the case used, but I need to extend this type of search to all the other columns, but so far everithing I use does not work.
I have tried:
$query = "SELECT * FROM Medios_table WHERE UPPER(id,Id_Nombre,Pais,Estado,Ciudad,website) LIKE UPPER('%$Busqueda%')";
$query = "SELECT * FROM Medios_table WHERE UPPER(concat(id,Id_Nombre,Pais,Estado,Ciudad,website)) LIKE UPPER('%$Busqueda%')";
$query = "SELECT * FROM Medios_table WHERE concat(UPPER(id,Id_Nombre,Pais,Estado,Ciudad,website)) LIKE UPPER('%$Busqueda%')";
etc.
any help is greatly appreciated, thanks.

Did you try UPPER around each column name? Like this:
$query = "SELECT * FROM Medios_table WHERE concat(UPPER(id),UPPER(Id_Nombre),UPPER(Pais),UPPER(Estado),UPPER(Ciudad),UPPER(website)) LIKE UPPER('%$Busqueda%')";

Your upper(concat(...)) version should work. If you had a problem with that, it's probably just a typo, like you left out a parenthesis or something.
You can't say upper(x,y,z) because upper takes only one parameter. You must do the concat first, then do the upper, i.e. upper(concat(x,y,z)).
That said, this query will be very slow on a big database, because the db engine has to read every record in the table, and then for each one search it character by character. If the table is small or this is done infrequently, that might be acceptable. If the table is big and/or this query will be executed often, you really need a totally different approach.
Update
If you really need to search against any text in a field, where you cannot make any assumptions about the text being searched in or the text being searched for in advance, you should investigate fulltext searches. http://dev.mysql.com/doc/refman/5.0/en/fulltext-natural-language.html
If you will be doing these sort of searches all the time, you might want to build a dictionary, that is, build a list of all the word with all the records that that word occurs in. I think that's basically what fulltext does, so this may or may not gain you anything.
But if you have some foreknowledge, that is, if it's not really that you want to search for arbitrary text occurring anywhere in arbitrary text, than break out the things you want to search for into separate fields.
To take a simple example, suppose you have a field that contains customer full name, like "Fred Smith", "Mary Jones", etc. You want to search for someone by last name. You could search for
where full_name like '%Smith%'
But this would require reading every record in the table. If, instead, you broke the field into first name and last name, then you could search for
where last_name='Smith'
If you have an index on last_name this would be a very fast search.
If you're just trying to look for an entered value in any of several fields, it is much, much faster to do
where estado='Toledo' or ciudad='Toledo' or pais='Toledo'
(assuming that you have indexes on estado, ciudad, and pais), then
where concat(estado, ciudad, pais) like '%Toledo%'
(where no index will do you any good).
If you want to do case-insensitive searches, create an index on upper(estado) instead of on estado, etc. Then "where upper(estado)='TOLEDO'" can use the index.
Also, I'm not sure about MySql, but some database engines can use an index if the LIKE does not begin with a wildcard. That is, "somefield like '%x%'" must read every record in the table. But on some db's, "somefield like 'x%'" can use can index to get to the records where the field starts with "x" and then just process those.

You need full-text search
This link may be useful Mysql full-text search