15 Quick Short Interview Questions Useful When Hiring SQL Developers - SQLServerCentral
To illustrate my point, I would cite the necessary sophistication of college entrance exams, SAT and ACT, or graduate school entrance exams, the LSAT, GRE, or MEDCAT tests. Hopefully everyone who takes this 10 or 15 minute test will learn something new from it, as well as go home and look up a few of these questions and answers
SQL Functions
Table 3-10 The Format Models with the ROUND Date Function Formal Model Rounding Unit CC or SCC Century YYYY, SYYYY, YEAR, SYEAR, YYY, YY, Y Year (rounds up on July 1) IYYY, IYY, IY, I ISO Year Q Quarter (rounds up in the sixteenth day of the second month of the quarter) MONTH, MON, MM, RM Month (rounds up on the sixteenth day) WW Same day of the week as the first day of the year IW Same day of the week as the first day of the ISO year W Same day of the week as the first day of the month DDD, DD, J Day DAY, DY, D Starting day of the week. EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO --------- ---------- --------- --------- --------- --------- --------- --------- 7698 BLAKE MANAGER 7839 1981-05-0 2950.52 30 3.3.66 TRANSLATE Syntax TRANSLATE(char, from, to) Purpose Returns char with all occurrences of each character in from replaced by its corresponding character in to, where char, from, and to are string arguments
PostgreSQL: Documentation: 9.4: Value Expressions
When an aggregate expression appears in a subquery (see Section 4.2.11 and Section 9.22), the aggregate is normally evaluated over the rows of the subquery. This means that they can contain variables only if those variables are grouped by GROUP BY; this restriction is the same as if the direct arguments were not inside an aggregate expression at all
25279 - PROC SQL Summary Functions
He also writes the popular SAS tips column "Kirk's Korner," which appears regularly in several SAS users group newsletters, and is a frequent speaker at SAS users group meetings. Summary Function Description AVG, MEAN Average or mean of values COUNT, FREQ, N Aggregate number of non-missing values CSS Corrected sum of squares CV Coefficient of variation MAX Largest value MIN Smallest value NMISS Number of missing values PRT Probability of a greater absolute value of Student's t RANGE Difference between the largest and smallest values STD Standard deviation STDERR Standard error of the mean SUM Sum of values SUMWGT Sum of the weight variable values, which is 1 T Testing the hypothesis that the population mean is zero USS Uncorrected sum of squares VAR Variance The next example uses the COUNT function with the (*) argument to produce a total number of rows, regardless of whether data is missing
Using the SQL MODEL Clause to Define Inter-row Calculations
Syntax Guidelines Note that the RETURN UPDATED ROWS clause following the MODEL keyword limits the results to just those rows that were created or updated in this query. Oracle Database 10g provides a mechanism to specify such conditions by allowing you to access cell values as they existed before and after the current iteration in the UNTIL condition
SQL 101: A Window into the World of Analytic Functions
A windowing clause is a set of parameters or keywords that defines the group (or window) of rows within a particular partition that will be evaluated for analytic function computation. Unlike the ROWS clause, the RANGE windowing clause can be used only with ORDER BY clauses containing columns or expressions of numeric or date datatypes
MySQL :: MySQL 5.0 Reference Manual :: 12.16.1 GROUP BY (Aggregate) Functions
(Before MySQL 5.0.3, SUM() and AVG() return DOUBLE for all numeric arguments.) The SUM() and AVG() aggregate functions do not work with temporal values. But if it's not indexed, SQL would have to evaluate each row individually anyway.You can take the idea a stage further by using a WHERE clause on the query too
The Product Aggregate in T-SQL Versus the CLR - CodeProject
The operators essentially set up 2,000 groups of all (rankNo, multiplier) pairings, and a Filter operator to come applies the recursive condition to determine the set of multipliers to use for each group. If you add one Compute Scalar operator on each side of the Stream Aggregate, you essentially have the plan for the EXP LOG code; subtract the Stream Aggregate, the CLR SIMULATION
Example queries: SELECT * FROM sp ORDER BY 3 DESC sno pno qty S1 P1 NULL S3 P1 1000 S3 P2 200 S2 P1 200 SELECT name, city FROM s ORDER BY name name city John London Mario Rome Pierre Paris SELECT * FROM sp ORDER BY qty DESC, sno sno pno qty S1 P1 NULL S3 P1 1000 S2 P1 200 S3 P2 200 Expressions In the previous subsection on basic Select statements, column values are used in the select list and where predicate. SQL Special Constructs SQL supports a set of special expression constructs: CAST(exp-1 AS data-type) Converts the value - exp-1, into the specified date-type
SQL Functions
If you call a SQL function with an argument of a datatype other than the datatype expected by the SQL function, then Oracle attempts to convert the argument to the expected datatype before performing the SQL function. See Also: "User-Defined Functions " and CREATE FUNCTION Single-Row Functions Single-row functions return a single result row for every row of a queried table or view
DBMSes provide additional aggregate functions to calculate other statistics, such as the standard deviation; search your DBMS documentation for aggregate functions or group functions. You apply an aggregate to a set of rows, which may be: All the rows in a table Only those rows specified by a WHERE clause Those rows created by a GROUP BY clause No matter how many rows the set contains, an aggregate function returns a single statistic: a sum, minimum, or average, for example
Majority of business reports will use more sophisticated reporting tools than the Query Analyzer or SQL Server Management Studio, therefore CUBE and ROLLUP extensions, as well as the GROUPING function have limited usage. The following query returns the sum of amounts from FactFinance table: SELECT SUM(Amount) FROM FactFinance Results: 1358640412.7 The next example uses DISTINCT keyword to return the sum of distinct values: SELECT SUM(DISTINCT Amount) FROM FactFinance Results: 1251597458.19 The SUM function returns the same (or a similar) data type as the group of values it accepts
My problem is, I don't want to Group By and I don't want to aggregate a column, I simply want to display the value of that column without it grouping and throwing everything else off. Because by the point at which the SELECT is done, the GROUP BY will have already aggregated those columns, and the SELECT can only choose from the ones that remain
One of the things one could do is instead of thinking in syntactical fashion is to start with the data and see where one needs to get to that could help one to get different solutions. Fill in your details below or click an icon to log in: Email (required) (Address never made public) Name (required) Website You are commenting using your WordPress.com account
Suwandi - Non Graduate Programmer Reply ijmar86 Member 410 Points 116 Posts Re: Column is invalid in the select list because it is not contained in either an aggregate funct... Suwandi - Non Graduate Programmer Reply SiakLang Member 4 Points 26 Posts Re: Column is invalid in the select list because it is not contained in either an aggregate funct..
sql server - Column is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause - Stack Overflow
What if you have 14 different values for column56: what should SQL Server guess that you want 14 rows in the output or collapse to MAX? The SQL standard requires the GROUP BY to be populated (of mainstream RDBMS, only MySQL doesn't and makes a guess to resolved the ambiguity). Obviously when I add them, MS SQL complains with the error: "Column 'applicationId' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause" Is there any way to add these computed value columns without having to change the other 100 columns in the select?? The example below is simplified but the original query is a lot bigger and more complex
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