Select 1 sql meaning.
May 16, 2022 · Table 'Users'.
Select 1 sql meaning.
There's no real technique to learn here.
Select 1 sql meaning You get this in a few scenarios including: Generated SQL: It's easier to create a generate a complex where statement if you don't have to work out if you're adding the first condition or not, so often a 1=1 is put at the beginning, and all other conditions can be appended with an And Dec 20, 2016 · It's just selecting the number "minus one" for each row returned, just like "select 1" will select the number "one" for each row returned. If your column is the result of a calculation it won’t have any name in the result, so you’ll have “(No column name)” If you want to give a (different) name to the column in the result you can use AS and alias name (SELECT 1+2 AS result;) Nov 18, 2013 · Think of it this way: For 'each' row from Suppliers, check if there 'exists' a row in the Order table that meets the condition Suppliers. SELECT last_name, employee_id FROM employee outer WHERE EXISTS (SELECT 'X' FROM employee manager_id=outer. If so, it evaluates to true. It's more a quirky use of a feature than an intended use of the XML formatting feature. SELECT 1 Means return 1 as the result set. Aug 3, 2009 · In SQL Server, these statements yield the same plans. NET CLR aggregate implementation where you implement the median and mode in, Feb 13, 2019 · $1 references the first parameter passed to the function, $2 would refer to the second and so on. Nov 28, 2024 · The select query in SQL is one of the most commonly used SQL commands to retrieve data from a database. Feb 5, 2024 · "SELECT 1 FROM TABLE" is a simple way to check if there are any rows in the specified MySQL table. It saves SQL Servers resources, e. Oct 28, 2008 · With the 1=1 at the start, the initial and has something to associate with. I have been a Java developer with knowledge on SQL for a couple years, but have never had to use unfamiliar statements like Select 1 or select count(1) Sep 10, 2013 · I am reading through some SQL Server stored procedures. * into SQL Server and it gave me Invalid column prefix '': No table name specified - you can, however, use a table alias so that it's SELECT a. Id from ( select SomeField1 as Id from dbo. select 1 from table; 을 하면 테이블의 10행 내용을 선택하는것이 아니라, 1이 10번 출력됨 여기서 1은 구체적인 데이터값으로써 의미를 부여하기는 어렵고, 값의 존재여부인 true false여부를 판단하는데 "사용"된다고 보는것이 맞음. It's just a cute trick to concatenate multiple rows of data into a single string. Syntax: SELECT COUNT(1) FROM table_name; Explanation: When using COUNT(1), SQL Server evaluates each row as "true" because 1 is always a non-null Jun 22, 2021 · The * means "all columns". – Apr 18, 2014 · Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand Nov 8, 2021 · SELECT refers to attributes that you want to have displayed in your final query result. EmpID, E. In the above example, the conditions related to age and location are commented out for the testing process, which allows the queries to be executed without considering the conditions. 2 Oct 2, 2011 · In general, Select 'X' is used with the EXISTS, as the EXISTS predicate does not care about the values in the rows but just if those rows exist. May 23, 2015 · SELECT $4 SQL server will return 4. Ask Question Asked 4 years, 10 months ago. Check this link which has some interesting comments on the usage of select null with Exists: SQL SERVER- IF EXISTS(Select null from table) vs IF EXISTS(Select 1 from table) Feb 26, 2008 · Many times I have seen issue of SELECT 1 vs SELECT * discussed in terms of performance or readability while checking for existence of rows in table. I think smart readers of this blog will come up the situation when SELECT 1 and SELECT * have different execution plan when used to find Oct 4, 2024 · Debugging without 1=1 would mean that you have to modify the With 1=1: SELECT * FROM Employees WHERE 1=1--AND Department = 'Sales The use of 1=1 in SQL WHERE clauses is a practical May 17, 2013 · 1=1 will always be true, so the value="TOYOTA" bit is the important one. Have you ever seen a WHERE 1=1 condition in a SELECT query. In this case, it returns the number of rows that meet the criteria specified in the “WHERE” clause. Scan count 1, logical reads 44440. 5 Lesley 7000. SELECT TOP 1 1 FROM [SomeTable] WHERE <SomeCondition> Means if the condition is true and any rows are returned from the select, only return top 1 row and only return integer 1 for the row (no data just the integer 1 is returned). You can always use parenthesis and aliases (as some_cool_name) to make thing clearer, or to change names in the result. But now, some filtering is being applied and of the 1 * 512 rows, only 43% are ultimately being returned. Jul 21, 2014 · SELECT pass from users WHERE user_name = 'admin' or (1=1) -- 'and permission='superadmin' Normally, (if the 1=1 hadn't been injected), you'd pull the password for the user with user_name of admin and superadmin permissions. Subqueries are legal in a SELECT statement's FROM clause. UPDATE: Also when i run this query in SQL Server, i get this; The query uses non-ANSI outer join operators ("*=" or "=*"). MyISAM tables are stored with a separate row count, so to do this query MySQL doesn't need to look at any of the table row data at all. select scores. exists checks if there is at least one row in the sub query. It doesn't retrieve any data from the table but rather returns a result set with a single column containing the value 1 for each row that satisfies the conditions in the WHERE clause (if any). SELECT id, name FROM users; they use. Why would someone use WHERE 1=1 AND in a SQL clause? “where 1=1” statement; Note that WHERE 1 is identical to WHERE 1=1; both mean WHERE TRUE but the former is rejected by many database management systems as not really being boolean. Jan 30, 2015 · The EXISTS keyword, as the name suggests, is used to determine whether or not any rows exist in a table that meet the specified condition. Therefore you can SELECT whatever you want, and canonical ways to do that include SELECT NULL or SELECT 1. Mar 13, 2013 · DUAL is a built-in table, useful because it is guaranteed to return only one row. PK ) For instance : Data Vault Hands On – First approach – Power BI Expert (powerbixpert. In this article, we’ll give an intro to the SELECT statement and we’ll cover more complex stuff in the upcoming articles. Sep 24, 2023 · Benefits of Using ‘WHERE 1=1’ Clause. : 'IF EXISTS ( SELECT 0 FROM Deleted )' will immediately break and return true after first row is found (will then return the '0'). Aug 20, 2017 · CREATE TABLE EMPL_DEMO AS SELECT * FROM employees WHERE 1=2; //just structure not data CREATE TABLE EMPL_DEMO AS SELECT * FROM employees WHERE 1=1; //ststructure and data Better understanding in the Teradata Database: Oct 29, 2020 · In other words, COUNT(1) assigns the value from the parentheses (number 1, in this case) to every row in the table, then the same function counts how many times the value in the parenthesis (1, in our case) has been assigned; naturally, this will always be equal to the number of rows in the table. Jun 5, 2014 · The overwhelming majority of people support my own view that there is no difference between the following statements:. Is there any negative effect when leaving out the offset/how is it possible to leave it out in the first place? This is very weird, so I could use a pair of spare eyes to understand what's happening. SELECT socialmedia_kat_stundenvorlagen. At Jul 20, 2019 · SQL Server allows you to sort the result set based on the ordinal positions of columns that appear in the select list. Among these are documentation for multiple releases of DB2. Contrary to whatever coding guidelines you are looking at, COUNT(*) is the preferred way of counting all the rows. network = network1 AND NV. Let us see an example. Jan 23, 2016 · In sql when we create a table there we define few things ex- create table tbl_employee ( id primary key identity(1,1) name varchar(50), age int, mobileno bigint ) select 1 from table will return the constant 1 for every row of the table. Id *= t2. Same logic turns sum(2) to 20 (that's 2 * 10), and so on. eg:- IF EXISTS( select null from ) It sets up the Exists status as true if there are records in the select query. To say the least, it is quite unclear what the actual intent of this query is. EDIT I've looked further into this, ASSUMING that I'm right with my assumption and . SELECT 1 FROM TABLENAME WITH (1) Oct 12, 2023 · However, you may be surprised to learn that you can also utilize syntax like ORDER BY 1 in a SQL query. For example, If any table has 4 records then it will return 1 four times. x = tableB. The COUNT function returns the number of rows for which the expression evaluates to a non-null value. The only, but important news for me was about column security checking. Sep 15, 2010 · Sometimes phpMyAdmin generates queries like: SELECT * FROM `items` WHERE 1 LIMIT 0 , 30 I wonder if WHERE 1 has any meaning in a query like that. The syntax for such a query is as follows: SELECT column_name(s) FROM table_name ORDER BY 1; If you've seen this kind of code in SQL queries and it left you puzzled, don't worry! Nov 22, 2024 · Line 1: “SELECT COUNT(*)” is a SQL aggregation function that returns the total number of rows in a table. The actual syntax is: SELECT FROM (subquery Feb 13, 2016 · The intention is an unconditional LEFT JOIN, which is different from a CROSS JOIN in that all rows from the left table expression are returned, even if there is no match in the right table expression - while a CROSS JOIN drops such rows from the result. In my test database, t_even is a table with 1,000,000 rows Sep 10, 2009 · UPDATE: Given the clarification the original poster made in their comment, the short, definitive answer is that a SELECT 1 or SELECT COUNT(1) is no faster than a SELECT COUNT(*). The condition obviously means WHERE TRUE, so it's just returning the same query result as it would without the WHERE clause. But instead of specifying the column names explicitly, it uses the ordinal positions of the columns: Sep 27, 2024 · 2. 4 Finch 10000. Please have a look at this one: select top 1 t. *, [column list from table b] with a proper JOIN. 33 ms) since midnight (for the time) *. y) SELECT * FROM tableA WHERE EXISTS (SELECT 1 FROM tableB WHERE tableA. There are different 'SELECT' statements such as 'SELECT DISTINCT' which returns only unique values (if there were duplicate values in the original query result) FROM basically means from which table you want the data. 1 Geeks 10000. One more thing, you could also check EXISTS (SELECT 1/0 FROM A) and you will see 1/0 is actually not executed. In this case, joining to the three underlying tables: syspalnames, syssingleobjrefs, and sysschobjs. Country_ID Jun 29, 2021 · select * from employee e where not exists (select 1 from employee e2 where e2. Selecting information is arguably the most important SQL feature. COUNT(1) The COUNT(1) also counts all rows in the table, just like COUNT(*), and ignores any NULL values. score, ranks. W3Schools offers free online tutorials, references and exercises in all the major languages of the web. In any other context, 1=1 is generally harmless, but not particularly useful. network IS NULL Oct 8, 2008 · The parameter to the COUNT function is an expression that is to be evaluated for each row. I ran quick 4 tests about this observed that I am getting same result when used SELECT 1 and SELECT *. Jul 3, 2013 · Select * from TableA t1, TableB t2 where t1. * means "select all columns from the socialmeda_kat_stundenvorlagen table". A simple SELECT * will use the clustered index and fast enough. Sep 10, 2018 · I was doing rank score problem at leetcode and I am not sure below solution. Dec 31, 2024 · What is GROUP BY 2 in SQL? GROUP BY 2 means grouping the query results by the second column or expression specified in the SELECT statement. Rounding Down Oct 14, 2013 · SELECT TOP 1 Means Selecting the very 1st record in the result set . For instance, under the column topic, I have the classifications of 'Chair', 'Metabolomics', 'Proteomics', and 'Endocrine'. You've now commented that out, and it isn't executed. Note that an alternative to your query is: SELECT count(*) INTO miss FROM billing b LEFT JOIN vas NV ON NV. Jul 3, 2015 · SELECT * FROM table LIMIT 0, 1 SELECT * FROM table LIMIT 1 The first argument should be considered as the offset if I'm not wrong, the purpose of those two queries is to limit the selection to up the first row of table. When you use 1=1 as the condition, it essentially means where true. SomeTable where SomeField2 = @someVariable union select -1 as Id ) t This is how I understand it: return first item returned by query. objects select top 1 1 from sys. In an EXISTS subselect, the database does not actually "retrieve" rows, and it does not always need to scan the entire result set for the subselect, because just one row will provide an answer. rank from scores left join ( select score, @x := @x +1 as rank from (select distinct score from scores order by score desc) s, (select @x := 0) r ) as ranks on scores. Jul 30, 2018 · In MySQL, I use <> to preferentially place specific rows at the front of a sort request. The number refers to the position of the column in the SELECT list. For example:-Q. What does || do in this statement?. Oct 22, 2023 · What does it mean by select 1 from MySQL table - The statement select 1 from any table name means that it returns only 1. Feb 4, 2012 · With the 1=1 at the start, the initial and has something to associate with. Query: SELECT * from myTable . This takes advantedge of the fact that SQL Server stores dates as two integers, one representing the number of days since day "0" - (1 jan 1900), and the second one which represents the number of ticks (about 3. and the prefix it means "all columns from the table/alias named". I have, within many different queries and across many SQL engines. The order of the results without an Order By clause is arbitrary. I've never seen this used for any kind of injection protection, as you say it doesn't seem like it would help much. Line 2: “INTO miss” is a SQL statement that assigns the result of the “SELECT COUNT(*)” to a variable named “miss”. Find employees who have at least one person reporting to them. May 4, 2023 · What Does "WHERE 1=1" Mean? In SQL, the WHERE clause is used to filter records based on a specific condition. score order by scores. So SQL Server is taking the use of $ and assuming we want to create a field with the MONEY datatype and as we haven't entered a value after the currency symbol, SQL Server assumes the value is 0, though in my opinion this should return NULL. 4 Finch 10000 Sep 11, 2015 · select top 1 * from sys. So in your case. com) Sep 20, 2010 · At the top of the page is a link to "IBM Manuals". So, using TOP in EXISTS is really not a necessary. I’m glad you’re still with me on this journey into the world of SQL queries. Let’s dive right into some fascinating benefits of using the WHERE 1=1 clause in your SQL statements. field SomeField1 will have an alias: Id Nov 8, 2021 · Nov 8, 2021 by Robert Gravelle. order by salary desc . The query plan without it is just a constant scan, and it does 0 reads. May 27, 2021 · I am modifying some SQL code and I have come across the statement: SELECT 'pilot' || cast(id as string) AS id from . If there is a query that has no conditions defined people (and specially ORM frameworks) often add always-true condition WHERE 1 = 1 or something like that. In other words, it returns all the records from the table without any MySQL, SQL, PL/SQLにおけるSELECT 1 FROM tableは、主にレコードの存在確認や単純なブール値の取得に使用されます。単純なブール値の取得 常に1を返すため、単純なブール値（真または偽）の取得に使用できます。 Jul 25, 2014 · @OMG Ponies@ "MySQL permits ORDER BY in views" -- MySQL permits a CHECK constraint in a CREATE TABLE but it doesn't actually honour it -- it never actually gets checked! The question is, do these SQL products always honour the ORDER BY in views e. The following statement sorts the customers by first name and last name. Without the TOP 1, the table scan will continue right through to the end. Apr 29, 2024 · SELECT * FROM users WHERE 1 = 1-- AND age > 30-- AND location = 'New York' ; Code language: SQL (Structured Query Language) (sql) Simple Debugging. That is merely a syntactic aspect. Select the SQL Reference for your release and search for WHERE EXISTS (the flashlight/tubelight near the top left). EmpName, Country = CASE WHEN T. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more. y) SELECT * FROM tableA WHERE Feb 5, 2024 · Description "SELECT 1 FROM TABLE" is a simple way to check if there are any rows in the specified MySQL table. Title Authors ----- ----- SQL Examples and Guide 4 The Joy of SQL 1 An Introduction to SQL 2 Pitfalls of SQL 1 Under the precondition that isbn is the only common column name of the two tables and that a column named title only exists in the Book table, one could re-write the query above in the following form: Mar 26, 2018 · On top of the nice explanation, 'select 1' means 'select the first column', in case there is confusion to new user. Expressions in the where clause are not part of the output columns, they just control which records should be included. It's useful when you want to cheaply determine if record matches your where clause and/or join. Aug 12, 2009 · I've seen that a lot in different query examples and it goes to probably all SQL engines. salary > e. You can do that so you get only the specific columns fro Jan 24, 2020 · Nice writing, thanks. Jan 13, 2020 · You can perform mathematical operations in SQL (SELECT 1+2;). It’s used to return results from our database(s) and no matter how easy that could sound, it could be really very complex. Sep 16, 2008 · a more general situation: basically, when we need to use any PL/SQL procedure inside a standard SQL statement, or when we want to call a procedure from the command line: select my_function(<input_params>) from dual; both recipes are taken from the book 'Oracle PL/SQL Recipes' by Josh Juneau and Matt Arena Jul 9, 2014 · It also means that the size of the variable is 2 bytes per character instead of 1 byte per char like a varchar() variable would be. In the same manual is lots of discussion about SELECT (probably much more than you want - but it is there) Jul 11, 2019 · IF 1=1 is in the WHERE condition it will not add a column of true values to the output, it literally means: select the record when 1 = 1, in short show all records. SELECT 1 Means return 1 as the result set . There was an old myth that a COUNT(1) was faster. Median(DataValues_AttributeValue) from There is no slick way to get the median or mode in a manner similar to using the native aggregates such as avg, max, min, max, etc. Dec 29, 2016 · If table T has columns C1 and C2 and you are checking for existence of row groups that match a specific condition, you can use SELECT 1 like this: EXISTS ( SELECT 1 FROM T GROUP BY C1 HAVING AGG(C2) = SomeValue ) but you cannot use SELECT * in the same way. May 2, 2012 · select * from sysobjects WITH (1) --Warning: Index hints supplied for view 'sysobjects' will be ignored. Viewed 3k times 1 . PK = t2. As to the preference of what you put inside your EXISTS subqueries - SELECT 1 or SELECT * - it doesn't matter. Just for kicks and giggles, I put the SELECT . So I have this query: WITH x as ( SELECT num_aula, tipo_aula, min(abs(capienza-1)) score Feb 15, 2017 · In step 2 those jobs were joined to a user. The parentheses can contain any value; the only Apr 30, 2020 · The SQL code is a query that returns true or false depending on wether an element with the id equal to :id (this is a paremter that needs to be bound when executing the query) exists in the table "favoritelist" or not. Then in your outer query you can refer to columns like: SELECT b. Of course, adding the 1 = (SELECT 1) thing to the end introduces full optimization, and prevents this. y) SELECT * FROM tableA WHERE EXISTS (SELECT y FROM tableB WHERE tableA. Aug 10, 2011 · Select * from – will retrieve all the columns of the table. select 1 from table will return the constant 1 for every row of the table. You have 10 rows, so this produces 10 - in other words this is 1 * 10. Nov 20, 2020 · When you think about learning SQL, one of the first things you come across is the SELECT statement. dep_id_fk = e. SELECT id, name FROM users WHERE 1 = 1; Oct 3, 2011 · SELECTing 1 or NV. Sep 12, 2020 · select patientID, count(1) from dbo (nolock) where admissiontime between '2020-01-31' and '2020-02-01' patientID in (0, 1) /* 0 means arthritis 1 means asthma */ So above query is used to find how many times there was a request from hospital for both asthma and arthritis related case. – Jan 14, 2015 · @jkonst: sometimes it`s better to use 'SELECT 0' than COUNT() because of the performance gain when used together with 'EXISTS'. network WHERE b. SELECT E. e. ID NAME SALARY. Active = 'N' AND 1 = 2 THEN 'Not Working Anymore' ELSE C. pass FROM (SELECT pass FROM table_name WHERE ssid=?) AS b See manual. Id Can anyone explain me, if such type of any query exists, if so then how its works. May 29, 2014 · One suggestion, when using EXISTS NOT EXISTS, it's not necessary to use SELECT TOP 1 there. if, in proc sql in SAS I create a table Jan 30, 2009 · SELECT TOP 1 will mean the table scan stops as soon as the one item is found. Very important point in fact: "for EVERY row in the table". With the select command in SQL, users can access data and retrieve specific records based on various conditions, making it an essential tool for managing and analyzing data. score desc; Jan 9, 2014 · Having a predefined WHERE clause with 1=1 in it allows additional WHERE conditions to be added to the SQL without having to check for the existence of a WHERE clause first, and the SQL engine will generally optimize out the 1=1 so there's no performance difference. What does ORDER BY 1 mean in SQL? ORDER BY 1 sorts the query results based on the first column or expression in the SELECT statement. Jan 8, 2016 · select 1 from table will return a column of 1's for every row in the table. Jul 16, 2011 · It will add one day. Any change in the referenced table would cause a change in the returned result set using *. Oct 23, 2023 · はじめに データベースとのやりとりにおいて、私が誤解したあるSQLの動作についてお話しします。それは、SELECT 1 FROM table というクエリです。一見すると、このクエリは1つだけの1を返すように思えるかもしれませんが、その実際 Dec 30, 2016 · SELECT 1 FROM table SELECT count(1) FROM table SELECT count(*) FROM table I looked up on stack overflow but couldn't find a satisfactory answer. Feb 2, 2011 · Select null is usually used in combination with EXISTS. So, your example will return an arbitrary RequestID (i. The issue with * relates to insert statements with existing tables or select statements used in a static report template. Oct 17, 2002 · SELECT 1 or SELECT * or SELECT NULL are constructions commonly used in an EXISTS subselect. Contrary to the popular opinion, in Oracle they do too. BTW, I think for an EXISTS subquery the security on the columns should not be checked if the column is referenced (either implicitly by * or explicitly) only in the SELECT list as it is not sent back to the caller. Country_ID = C. 3 David 16000. g. select 1 from – will retrieve 1 for all the rows. This means DUAL may be used to get pseudo-columns such as user or sysdate, the results of calculations and the like. Because i have never seen such type of query Thanks. Mar 1, 2013 · Someone please explain the meaning of '1=2' in the below SQL query. – Katherine Chen Commented Nov 25, 2021 at 16:53 Dec 31, 2013 · 1 Geeks 10000. 2 RR 6000. score = ranks. supplier_id. However, you may want to try a . employee_id) May 15, 2020 · Well, sum(1) does just what it says: sum() fixed integer value 1 across all rows in the table. But if the variable was previously declared as a Unicode variable ( declare @sqlString nVarchar(200) ), then I don't think you need to prefix the string literal with the N . salary); My reasoning: First, a subquery will be executed and Postgres will save this temporary result May 19, 2009 · The query in the example will return the first RequestID from the table PublisherRequests. Modified 4 years, 9 months ago. Sep 11, 2016 · Yes, they are the same. There can be one or many tables listed There's no real technique to learn here. I have seen it used as an implementation convenience. Contract_No = E. You could use it with a where statement to check whether you have an entry for a given key, as in: if exists(select 1 from table where some_column = 'some_value') Nov 18, 2016 · SELECT 1 just selects a 1, of course. I can understand every part except for @x := @x +1 and @x := 0. network will return the same number of rows. the first RequestID in an arbitrarily ordered list of RequestIDs). SYS_GUID() in Oracle is quite computation intensive function. In this article, we’ll demonstrate the typical use cases for SQL SELECT with practical examples. Using TOP 1, it should on average be 50% quicker than not using TOP 1. dep_id_fk and e2. What it's used for in this case is testing whether any rows exist that match the criteria: if a row exists that matches the WHERE clause, then it returns 1, otherwise it returns nothing. I imagine that you may rather want to do something like this: select dbo. Apr 5, 2020 · Meaning of "select c. Dec 10, 2020 · SELECT TOP 1 Means Selecting the very 1st record in the result set. The SQL query engine will end up ignoring the 1=1 so it should have no performance impact. SELECT 1 FROM TABLENAME(1) Equals. May 16, 2022 · Table 'Users'. The use of $1 as a parameter "name" predates the introduction of named parameters for SQL functions in Postgres 9. Sep 15, 2015 · SELECT 1 FROM (SELECT pass FROM table_name WHERE ssid=?) AS b WHERE pass=? b is alias name for subquery. Country_Name END, T. I thought it would replace falsey values by 'pilot'; but that is not the case, it returns NULL values. Since 1 is a constant and not associated with any column, it does not check for NULL s. Contract_No LEFT JOIN Country C (nolock) ON E. Since we only need to filter out those rows which meet the condition, but do not need to actually retrieve the values of individual columns, we use select 1 instead. There was only 1 user that matched, so your intermediary result is 1 user * 512 jobs. network = b. I'm studing SQL in the context of ETL jobs and I really don't understand why so many books and blogs use the syntax : SELECT FROM table1 t1 WHERE EXISTS ( SELECT 1 FROM table2 t2 WHERE t1. It means you have done a query that does nothing more than count the number of rows in a table, and that table is a MyISAM table. In the final join (eq_ref) where you are joining to your item table, there is 1 item rows that qualify. fetch first 3 rows only; Output: We got only first 3 rows order by Salary in Descending Order. Jan 13, 2020 · The SELECT statement is probably the most important SQL command. " in SQL. 00. The columns in the sub query don't matter in any way. As with anything that involves scanning (or brute force) to do the search. SELECT * FROM tableA WHERE EXISTS (SELECT * FROM tableB WHERE tableA. Since the equality condition 1=1 is always true, the WHERE clause does not filter out any records. Jun 8, 2011 · MAX(x) - 1 simply means the max value of x in the table minus one. Combined with the . when used in a query that also has an ORDER BY does it get sorted twice? Jul 26, 2011 · It means "Select All", referring to all columns in referenced table. objects The first one will be slower because it has to actually return real data. Contract_No FROM Employees E (nolock) INNER JOIN Contract T ON T. There is nothing special about the "select 1" syntax uses in EXISTS statements by the way; it's just selecting some random value because EXISTS requires a record to be returned and a record needs data; the number 1 is sufficient. 6 Watson 10000. So instead of. . supplier_id (this comes from Outer query current 'row') = Orders. vdnhdwumuobbqkrtmrixqtxzvbjmlaxoimywvnbwqnqjs