Question

我在使用LIKE搜索SQL时遇到问题。我希望SQL LIKE搜索所有可以混合的字符。让我给你演示。数据库用户：

  pkg load statistics

% create 1000 samples from a known multivariate normal
  Observations     = mvnrnd( [0,0], [4, 1; 1 ,2], 1000 );

% Get mean and covariance estimates from sample
  SampleMean       = mean( Observations, 1 ) % average along rows
  SampleCovariance = cov( Observations )

% Get mean and standard deviation in first dimension (i.e. "x-axis")
  Mean_firstDimension   = SampleMean(1)
  StdDev_firstDimension = sqrt( SampleCovariance(1,1) )

% Get gaussian values at malanobis distance of 1, 2, and 3
  MVN_value_at_mahalanobis_distance_of_one   = mvnpdf( [ Mean_firstDimension +     StdDev_firstDimension, 0], SampleMean, SampleCovariance )
  MVN_value_at_mahalanobis_distance_of_two   = mvnpdf( [ Mean_firstDimension + 2 * StdDev_firstDimension, 0], SampleMean, SampleCovariance )    
  MVN_value_at_mahalanobis_distance_of_three = mvnpdf( [ Mean_firstDimension + 3 * StdDev_firstDimension, 0], SampleMean, SampleCovariance )    

% Define grid:
  [GridX, GridY] = ndgrid( -8:0.1:8, -8:0.1:8 );
  GridValues = mvnpdf( [GridX(:), GridY(:)], SampleMean, SampleCovariance );
  GridValues = reshape( GridValues, size( GridX ) );

% Plot Observations
  plot( Observations(:,1), Observations(:,2), 'o', 'markerfacecolor', 'g', 'markeredgecolor', [0,0.5,0], 'linewidth', 1.5 );
  hold on;

% Plot contours over grid
  contour( GridX, GridY, GridValues,   ...
           [ MVN_value_at_mahalanobis_distance_of_three, ...
             MVN_value_at_mahalanobis_distance_of_two, ...
             MVN_value_at_mahalanobis_distance_of_one ...
           ],
           'linewidth', 2
  )
  hold off;

% Set nice limits and colours for background
  axis([-8, +8, -8, +8]); axis equal square;
  set(gca, 'color', 'k');
  set(gcf, 'color', [0.75, 0.75, 0.75]);

SQL是：

----------------------------------------------
id   fname   lname   phoone   email
----------------------------------------------
1    John    Smit    51451    john@gmail.com
----------------------------------------------
2    Maria   Doul    878988   maria@gmail.com
----------------------------------------------
3    Bob     Coul    879333   bob@gmail.com
----------------------------------------------

上面的SQL运行正常。但我也想像这样严谨地搜索：

SELECT * FROM users WHERE CONCAT(fname, lname, phone, email) LIKE
'%Smi%514%'

上面的SQL返回NULL，因为在CONCATENATION中，“ John”在“ Smi”之前。有什么方法可以使SQL查询以两种方式进行搜索。

Answer 1

每个搜索词都需要一个单独的like，如下所示：

SELECT * 
FROM users 
WHERE CONCAT(fname, lname, phone, email) LIKE '%Smi%'
    AND CONCAT(fname, lname, phone, email) LIKE '%514%'
    AND CONCAT(fname, lname, phone, email) LIKE '%John%'

Answer 2

也考虑

FULLTEXT(fname, lname, phone, email)

与

一起

MATCH(fname, lname, phone, email) AGAINST('+John +Smith +514' IN BOOLEAN MODE)

使用LIKE在SQL中搜索

2 个答案: