enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Aggregate function - Wikipedia

    en.wikipedia.org/wiki/Aggregate_function

    In database management, an aggregate function or aggregation function is a function where multiple values are processed together to form a single summary statistic. (Figure 1) Entity relationship diagram representation of aggregation. Common aggregate functions include: Average (i.e., arithmetic mean) Count; Maximum; Median; Minimum; Mode ...

  3. Mode (statistics) - Wikipedia

    en.wikipedia.org/wiki/Mode_(statistics)

    Like the statistical mean and median, the mode is a way of expressing, in a (usually) single number, important information about a random variable or a population. The numerical value of the mode is the same as that of the mean and median in a normal distribution, and it may be very different in highly skewed distributions.

  4. Log-normal distribution - Wikipedia

    en.wikipedia.org/wiki/Log-normal_distribution

    Comparison of mean, median and mode of two log-normal distributions with different skewness. The mode is the point of global maximum of the probability density function. In particular, by solving the equation ( ln ⁡ f ) ′ = 0 {\displaystyle (\ln f)'=0} , we get that:

  5. Shewhart individuals control chart - Wikipedia

    en.wikipedia.org/wiki/Shewhart_individuals...

    In statistical quality control, the individual/moving-range chart is a type of control chart used to monitor variables data from a business or industrial process for which it is impractical to use rational subgroups. [1] The chart is necessary in the following situations: [2]: 231

  6. Central tendency - Wikipedia

    en.wikipedia.org/wiki/Central_tendency

    the weighted arithmetic mean of the median and two quartiles. Winsorized mean an arithmetic mean in which extreme values are replaced by values closer to the median. Any of the above may be applied to each dimension of multi-dimensional data, but the results may not be invariant to rotations of the multi-dimensional space. Geometric median

  7. Comparison of data modeling tools - Wikipedia

    en.wikipedia.org/wiki/Comparison_of_data...

    Update database and/or update model No Navicat Data Modeler Conceptual, Logical & Physical IE (Crow’s foot) Yes Yes Update database and/or update model No NORMA Object-Role modeling Conceptual (ORM), Logical, Physical ORM, Relational(Crow’s foot option), Barker Yes Yes Update database and/or update model No Open ModelSphere

  8. SQL-92 - Wikipedia

    en.wikipedia.org/wiki/SQL-92

    SQL-92 was the third revision of the SQL database query language. Unlike SQL-89, it was a major revision of the standard. Aside from a few minor incompatibilities, the SQL-89 standard is forward-compatible with SQL-92. The standard specification itself grew about five times compared to SQL-89.

  9. Database theory - Wikipedia

    en.wikipedia.org/wiki/Database_theory

    Database theory encapsulates a broad range of topics related to the study and research of the theoretical realm of databases and database management systems.. Theoretical aspects of data management include, among other areas, the foundations of query languages, computational complexity and expressive power of queries, finite model theory, database design theory, dependency theory, foundations ...