Keys definition at Dictionary.com, a free online dictionary with pronunciation, synonyms and translation. About Florida Keys Stretching 126 miles south toward Cuba, the stunning Keys are a perfect escape. Highlights along the way include Key Largo, Islamorada, Marathon, Big Pine Key and the irrepressible Key West. Get up close with an amazing array of fish while snorkeling, diving.
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a. A notched and grooved, usually metal implement that is turned to open or close a lock.
b. A similar implement or an electronic device used for opening, winding, or starting something: the key of a wind-up alarm clock; the new car's electronic key.
c. A device, such as a wedge or pin, inserted to lock together mechanical or structural parts.
2. A determining factor in accomplishing or achieving something: One key to the store's success has been consistent customer service.3.
a. Something that provides access to or understanding of something else: The key to the mystery was a drug store receipt.
c. A table, gloss, or cipher containing correspondences, as for decoding or interpreting something.
d. Computers A number used by a cryptographic algorithm to encrypt or decrypt data.
4. Architecture The keystone in the crown of an arch.5.
a. A button or lever that is depressed to operate a machine.
b. A button that is depressed to cause a corresponding character or function to be typed or executed by a typewriter or to be accepted as input by a computer.
c. Music A button or lever that is depressed with the finger to produce or modulate the sound of an instrument, such as a clarinet or piano.6.
a. A tonal system consisting of seven tones in fixed relationship to a tonic, having a characteristic key signature and being the structural foundation of the bulk of Western music; tonality.
b. The principal tonality of a work: an etude in the key of E.
8. A characteristic tone or level of intensity, as of a speech or sales campaign. Often used in combination: high-key; low-key.
10. An outline of the distinguishing characteristics of a group of organisms, used as a guide in taxonomic identification.
11. Basketball An area at each end of the court between the baseline and the foul line and including the jump-ball circle at the foul line: a jump shot from the top of the key.
12. The act of replacing portions of a video or photograph containing a preselected color with material from a separate image, as by chroma key.adj.
Of crucial importance; significant: key decisions; the key element of the thesis.v.tr.
2. To be the determining or crucial factor in: a double that keyed a three-run rally in the fifth inning.
3. Architecture To furnish (an arch) with a keystone.
5. To bring into harmony; adjust or adapt: 'achievement tests that are more clearly keyed to what students are held responsible for in high school'(New York Times).
6. To cause to pay attention to: school officials who were keyed into the dietary needs of students.
7. To supply with a key of correspondences or with corresponding references: keyed the pages in the edited book to illustrations in the manuscript.8.
a. To operate (a device), as for typesetting, by means of a keyboard.
b. To enter (data) into a computer by means of a keyboard.
10. To vandalize or mar by scratching with a key: Vandals keyed the cars left in the parking garage.
11. To produce, replace, or include by chroma key.v.intr.
1. To pay close attention; focus: improved service by keying on customer complaints; keyed into the main points of the lecture.
2. Sports To watch or cover an opposing player closely in an effort to limit the player's effectiveness. Used with on:'[She] still carries the burden of scoring ... even though opponents key on her throughout every game'(Josh Barr).
3. To replace portions of a video or photograph containing a preselected color with material from a separate image, as by chroma key.Phrasal Verb: key up
To make intense, excited, or nervous: The actors were keyed up before the opening.Idioms:
out of key
[Middle English kai, kei, from Old English cǣg.]
A low offshore island or reef, especially in the Gulf of Mexico; a cay.
[Alteration (influenced by key, variant of quay) of Spanish cayo; see cay.]
[Shortening and alteration of kilogram.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
dialectScot a children's cry for truce or respite from the rules of a game
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
Collins Multilingual Translator © HarperCollins Publishers 2009
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A key serves as a unique identifier for each entity instance. Most entities in EF have a single key, which maps to the concept of a primary key in relational databases (for entities without keys, see Keyless entities). Entities can have additional keys beyond the primary key (see Alternate Keys for more information).
Configuring a primary key
By convention, a property named
<type name>Id will be configured as the primary key of an entity.
Owned entity types use different rules to define keys.
You can configure a single property to be the primary key of an entity as follows:
You can also configure multiple properties to be the key of an entity - this is known as a composite key. Composite keys can only be configured using the Fluent API; conventions will never set up a composite key, and you can not use Data Annotations to configure one.
For non-composite numeric and GUID primary keys, EF Core sets up value generation for you by convention. For example, a numeric primary key in SQL Server is automatically set up to be an IDENTITY column. For more information, see the documentation on value generation.
Primary key name
By convention, on relational databases primary keys are created with the name
PK_<type name>. You can configure the name of the primary key constraint as follows:
Key types and values
While EF Core supports using properties of any primitive type as the primary key, including
byte and others, not all databases support all types as keys. In some cases the key values can be converted to a supported type automatically, otherwise the conversion should be specified manually.
Key properties must always have a non-default value when adding a new entity to the context, but some types will be generated by the database. In that case EF will try to generate a temporary value when the entity is added for tracking purposes. After SaveChanges is called the temporary value will be replaced by the value generated by the database.
If a key property has its value generated by the database and a non-default value is specified when an entity is added, then EF will assume that the entity already exists in the database and will try to update it instead of inserting a new one. To avoid this, turn off value generation or see how to specify explicit values for generated properties.
An alternate key serves as an alternate unique identifier for each entity instance in addition to the primary key; it can be used as the target of a relationship. When using a relational database this maps to the concept of a unique index/constraint on the alternate key column(s) and one or more foreign key constraints that reference the column(s).
Keystone Xl Pipeline
If you just want to enforce uniqueness on a column, define a unique index rather than an alternate key (see Indexes). In EF, alternate keys are read-only and provide additional semantics over unique indexes because they can be used as the target of a foreign key.
Alternate keys are typically introduced for you when needed and you do not need to manually configure them. By convention, an alternate key is introduced for you when you identify a property which isn't the primary key as the target of a relationship.
Florida Keys Vacations
You can also configure a single property to be an alternate key:
You can also configure multiple properties to be an alternate key (known as a composite alternate key):
Finally, by convention, the index and constraint that are introduced for an alternate key will be named
AK_<type name>_<property name> (for composite alternate keys
<property name> becomes an underscore separated list of property names). You can configure the name of the alternate key's index and unique constraint: