What Is The Maximum Possible Number Of Fields In A Table?
What is the theoretical and practical limits of number of fields in a table?
Say I have 1000 or 10000 integer fields in a table, does the query processing speed decrease?
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Maximum Number Of Fields
I'm trying to create a table with 21 fields and I'm failing miserably. Is there a maximum limit? Or am I just blind to a typo? here's the command (in PHP): $resultID = mysql_query("CREATE TABLE wordforms (WordForm CHAR(100), Language CHAR(100), Category CHAR(100), Lexeme CHAR(100), Case CHAR(100), Number CHAR(100), Gender CHAR(100), Person CHAR(100), Tense CHAR(100), VerbForm CHAR(100), Degree CHAR(100), Adjective CHAR(100), VerbStrength CHAR(100), VerbType CHAR (100), Modal CHAR(100), Conjunction CHAR(100), Preposition CHAR(100), VerbMotionStatic CHAR(100), VerbArguments CHAR(100), VerbTransitivity CHAR(100), VerbObjectCase CHAR(100))", $linkID);
Maximum Fields In A Table
I have a website which runs pretty slow... I have turned on the SLOW-QUERY-LOG, and there's one table that is in the log over and over again... It's the table which stores 99% of the user information. This table has 61 fields, and alot of these are varChar and their set at 100 or so.... Anyways, I was curious what is the maximum amount of fields you should have in table, and in my case should I split the data between several tables and just use a complex Join statement?
Get Maximum Number From A Field
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Print The Maximum Number
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Maximum Number Of Databases / Schema
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Find The Maximum Of The Sum Of Some Fields.
I want to select the biggest result which I get by adding the fields named "vote" with the same user_id. I thought of the following (but it didn't work out, unfortunately): SELECT max(sum(rating)) FROM votes WHERE user_id = $user_id Could anyone help me with this?
Using A Query To Determine The Maximum Value A Number Col Can Hold?
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I have a problem where I want to get no more than 10 (LIMIT) of the newest records from a table that are within a month, but I want to get at MINIMUM 3 records, all using SQL. I can do : ------------------- SELECT * FROM updates WHERE date_of_update BETWEEN DATE_SUB( CURDATE( ) , INTERVAL 1 MONTH ) AND CURDATE( ) ORDER BY date_of_update DESC LIMIT 0 , 10 ------------------- To limit it to the 10 updates no older than a month, but if there are no updates within a month I get nothing. So I would like to do something like : ------------------- SELECT * FROM updates WHERE ROWNUM() < 3 OR ((date_of_update BETWEEN DATE_SUB( CURDATE( ) , INTERVAL 1 MONTH ) AND CURDATE( )) AND update_id IN ( SELECT * FROM updates ORDER BY date_of_update DESC LIMIT 0, 10 )) ------------------- This code will take the 10 most recent updates and then starts pulling them out as long as the number of rows is less less than 3 or the update is within the date range and one of the 10 recent updates. The problem is that mySQL appears not to have any kind of rownum function. Limit is a nice substitute except it only works for setting an upper bound, not a lower bound number of records.
Maximum Number Of Databases In A Single Installation
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Maximum Number Of Columns And Actual Data In A Row
SUMMARY: I need to know what the actual maximum date limit possible on a row of a MYSQL database. MORE DETAILS: For example, does a MYSQL database only allow 4032 bytes of data to be stored in one row or is there no limit? Does it only allow a maximum of 50 colmums? I tried googling on this, but all the results seem to be about recommended maximums or design style. As an ex-Access developer I remeber hitting a limit with the Access DB which I think was that one row could contain 2048 bytes max(things like blobs do not contribute to this limit). I'm hoping there are no limitations with MYSQL. My reason for asking is that I have been asked to add new fields to someone elses DB. There are already a lot of columns and the short and dirty fix for me which would mean minimul PHP script changes is by adding new fields to the current table. But there are already quite a few so thought I would check.
Max Number Of Fields
I have product table , it has 40 fields , is it a bad thing to have that many fields? secondly On one page , I have 4 select statements, is it bad pratice to have so many select statemnts, it may slow down the page?
Maximum Rows In Table
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Query Fields That Start With A Number
I am building an index for our Client List page, which lists over 400 clients of ours. I want to change the SELECT query that returns the resultset that is shown to select ONLY records that start with a certain letter. This is being done with the addition of the following code to my MySQL query: $query_Clients .= "WHERE clientName LIKE '".$_GET['letter']."%' ";
Database Of Dynamic Number Of Fields
for instance a baseball game may have 9 or more innings, suppose you wanted to store like a boxscore for each date for both teams that played, any ideas for the best way to accomplish this? Im basically trying to pull the data of a box score from a mysql database, but not sure on what would be the best way to store. I hope that is clear enough. To sum it up: I basically want to maintain a database of every boxscore that can be accessed by clicking a link to the date and displaying it neatly in a table or such......
How To Find Number Of Non-null Fields In Each Record?
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Fields In One Table Overwrite Fields In Another Via JOIN
I'm writing a simple web game which uses mysql to store data. The prototype works ok so far, but now I'm refactoring it to support multiple players. This means coming up with a way to store the player's current world state. I'm thinking of doing this by having a table that defines the initial world state, and then a table containing the 'state' of anything different. Example: The 'objects' table looks like this: object_id, name, room 1, Hammer, 1 2, Mirror, 1 3, Spade, 2 So, at the start, room 1 contains a hammer and a mirror, and room 2 contains a spade. Now, if player 12 picks up the hammer then drops it in room 2, I store this override in the 'state' table player_id, object_id, room 12, 1, 2 So. I'm trying to see if there's any kind of join syntax that would return all the objects in a room for a given player's 'session'. Obviously it could be done with temporary tables, or just comparison outside of SQL, but I keep thinking this might be possible *somehow*
One Table With Many Fields Or Many Tables With Few Fields?
I need to build a database, but I'm torn between these 2 choices: Is it better to have one table which has many fields or many tables which each has few fields? Is it true that the latter is worse because it will require many join operations? What is the limitation of the first option (one table with many fields)?
Table Number Limit?
Is there a limit to the number of tables allowed in MySQL? Is there any non-obvious performance hit associated with having too many tables? Assume the data size will be the same. In other words, having a table that is 1.5Gig versus having 1000 tables that are each 1.5MB in size.
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Number Of Table Rows
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Trigger To Increase Number On Certain Row On Other Table
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