Work & Data Glossary
Understand the concepts that appear in SQL, Excel, inventory, production, data quality, SEO and web performance.
Primary Key
A column or set of columns that uniquely identifies a row in a table.
Open →DatabaseForeign Key
A column that references a key in another table to represent a relationship.
Open →DatabaseJoin Key
The field or fields used to match related rows between datasets.
Open →DatabaseCardinality
How many rows on one side of a relationship can match rows on the other side.
Open →SQLCTE
A named query expression defined with WITH for use inside one SQL statement.
Open →SQLWindow Function
A calculation across related rows that keeps row-level detail.
Open →SQLPARTITION BY
The clause that divides rows into independent windows for a window function.
Open →SQLAggregate
A summary calculation such as COUNT, SUM, AVG, MIN or MAX.
Open →SQLAnti Join
A pattern that returns rows from one set that have no match in another.
Open →SQLNULL
A marker for missing or unknown data, distinct from zero or an empty string.
Open →OperationsSKU
A stock keeping unit identifier used to distinguish inventory items.
Open →ProductionBOM
A bill of materials describing the components and quantities needed for an item.
Open →ProductionOEE
Overall Equipment Effectiveness: Availability × Performance × Quality.
Open →ProductionTakt Time
Available production time divided by customer demand.
Open →ProductionCycle Time
The elapsed time required to complete one process cycle or unit.
Open →QualityYield
Good output divided by total input or total produced quantity.
Open →QualityScrap Rate
Scrapped quantity divided by input or total quantity.
Open →OperationsLead Time
Elapsed time from a trigger such as order placement to completion or delivery.
Open →InventorySafety Stock
Extra inventory held to protect against demand or lead-time variability.
Open →InventoryReorder Point
Inventory position at which replenishment should be triggered.
Open →InventoryEOQ
Economic Order Quantity, a model balancing ordering and holding costs.
Open →InventoryStock Coverage
How long current stock can support demand, often measured in days.
Open →InventoryInventory Turnover
How often inventory value is sold or consumed during a period.
Open →InventoryABC Analysis
Classification of items by cumulative consumption value or another priority metric.
Open →ProcurementPurchase Order
A formal order document defining requested items, quantities and prices.
Open →ProcurementInvoice
A supplier billing document requesting payment for delivered goods or services.
Open →ProcurementPrice Variance
Difference between expected and actual unit price.
Open →OperationsQuantity Variance
Difference between expected and actual quantity.
Open →WarehouseHandling Unit
A uniquely identified physical logistics unit such as a pallet, case or container.
Open →SystemsERP
Enterprise Resource Planning software that integrates operational business processes.
Open →DataCSV
Comma-separated values: a plain-text format for flat tabular data.
Open →DataXLSX
The modern Excel workbook format supporting sheets, formulas, formatting and typed cells.
Open →DataDelimiter
A character such as comma, semicolon or tab that separates fields in a text file.
Open →DataText Encoding
The mapping used to represent characters as bytes, such as UTF-8.
Open →DataData Type
The intended kind of value such as text, integer, decimal, date or Boolean.
Open →Data QualityDuplicate Key
A key value that appears more than once when uniqueness is expected.
Open →Data QualityMissing Value
A field with no usable value, represented as blank, NULL or another missing marker.
Open →Data QualityOutlier
A value that differs substantially from the normal range or pattern.
Open →DataNormalization
Standardizing values or database structure to make matching and maintenance reliable.
Open →ExcelLookup
A formula or operation that finds a key and returns related information.
Open →ExcelXLOOKUP
A modern Excel lookup function with separate lookup and return arrays.
Open →ExcelVLOOKUP
A legacy Excel function that searches the first column of a table and returns a column to the right.
Open →ExcelINDEX MATCH
A lookup pattern combining MATCH for position and INDEX for return value.
Open →ExcelSUMIFS
An Excel function that sums values meeting multiple criteria.
Open →ExcelCOUNTIFS
An Excel function that counts rows meeting multiple criteria.
Open →ExcelDynamic Array
A formula result that can spill automatically into multiple cells.
Open →ExcelPivot Table
An interactive grouped summary of tabular data.
Open →ExcelPower Query
Excel’s repeatable import and transformation engine.
Open →ExcelAbsolute Reference
A cell reference locked with $ so copied formulas keep the same row and/or column.
Open →HTMLSemantic HTML
Markup elements chosen for the meaning and structure of content.
Open →AccessibilityARIA
Attributes that supplement accessibility semantics when native HTML is insufficient.
Open →SEOCanonical URL
The preferred URL declared for a page when multiple URLs could represent similar content.
Open →SEOStructured Data
Machine-readable metadata, commonly JSON-LD, describing entities on a page.
Open →Web PerformanceCore Web Vitals
User-experience metrics focused on loading, interaction responsiveness and visual stability.
Open →Web PerformanceLCP
Largest Contentful Paint, a metric for main-content loading performance.
Open →Web PerformanceCLS
Cumulative Layout Shift, a metric for unexpected visual movement.
Open →Web PerformanceINP
Interaction to Next Paint, a responsiveness metric for user interactions.
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